1993 World Trade Center bombing

WTC_1993_ATF_Commons

The World Trade Center bombing occurred on February 26, 1993, when a truck bomb was detonated below the North Tower of the World Trade Center in New York, NY. The 1,336 lb (606 kg) urea nitrate–hydrogen gas enhanced device was intended to knock the North Tower (Tower One) into the South Tower (Tower Two), bringing both towers down and killing thousands of people.

It failed to do so, but did kill six people and injured more than a thousand.The attack was planned by a group of conspirators including Ramzi Yousef, Mahmud Abouhalima, Mohammad Salameh, Nidal A. Ayyad, Abdul Rahman Yasin and Ahmad Ajaj. They received financing from Khaled Sheikh Mohammed, Yousef’s uncle.

In March 1994, four men were convicted of carrying out the bombing: Abouhalima, Ajaj, Ayyad and Salameh. The charges included conspiracy, explosive destruction of property and interstate transportation of explosives. In November 1997, two more were convicted: Ramzi Yousef, the mastermind behind the bombings, and Eyad Ismoil, who drove the truck carrying the bomb.

Planning and organization

Ramzi Yousef, who was born as Abdul Basit Mahmoud Abdul Karim in Kuwait, spent time at Al-Qaeda training camps in Afghanistan,[5] before beginning in 1991 to plan a bombing attack within the United States. Yousef’s uncle Khalid Shaikh Mohammed Ali Fadden, who later was considered the principal architect of the September 11 attacks, gave him advice and tips over the phone, and funded him with a US$1,400 wire transfer.

Yousef arrived illegally in the United States on September 1, 1992, traveling with Ahmed Ajaj from Pakistan, though both sat apart on the flight and acted as though they were traveling separately. Ajaj tried to enter with a forged Swedish passport, though it had been altered and thus raised suspicions among INS officials at John F. Kennedy International Airport. When officials put Ajaj through secondary inspection, they discovered bomb making instructions and other materials in his luggage, and arrested him. The name Abu Barra, an alias of Mohammed Jamal Khalifa, appeared in the manuals. Yousef tried to enter with a false Iraqi passport, claiming political asylum. Yousef was allowed into the United States, and was given a hearing date.

Yousef set up residence on Nicole Pickett Avenue in Jersey City, New Jersey, traveled around New York and New Jersey and called Sheikh Omar Abdel Rahman, a controversial blind Muslim cleric, via cell phone. After being introduced to his co-conspirators by Abdel Rahman at the latter’s Al-Farooq Mosque in Brooklyn, Yousef began assembling the 1,500 lb (680 kg) urea nitrate–hydrogen gas enhanced device for delivery to the WTC. He ordered chemicals from his hospital room when injured in a car crash – one of three accidents caused by Salameh in late 1992 and early in 1993.

El Sayyid Nosair, one of the blind sheikh’s men, was arrested in 1991 for the murder of Rabbi Meir Kahane. According to prosecutors, “the Red” Mahmud Abouhalima, also convicted in the bombing, told Wadih el Hage to buy the .357 caliber revolver used by Nosair in the Kahane shooting. In the initial court case in NYS Criminal Court Nosair was acquitted of murder but convicted of gun charges (in a related and follow-up case in Federal Court, he was convicted). Dozens of Arabic bomb-making manuals and documents related to terrorist plots were found in Nosair’s New Jersey apartment, with manuals from Army Special Warfare Center at Fort Bragg, North Carolina, secret memos linked to Joint Chiefs of Staff, and 1,440 rounds of ammunition. (Lance 2004 26)

Yousef’s view of the attack

According to the journalist Steve Coll, Yousef mailed letters to various New York newspapers just before the attack, in which he claimed he belonged to ‘Liberation Army, Fifth Battalion’.These letters made three demands: an end to all US aid to Israel, an end to US diplomatic relations with Israel, and a pledge by the United States to end interference “with any of the Middle East countries’ interior affairs.” He stated that the attack on the World Trade Center would be merely the first of such attacks if his demands were not met. In his letters Yousef admitted that the World Trade Center bombing was an act of terrorism, but this was justified because “the terrorism that Israel practices (which America supports) must be faced with a similar one.”

The attack

On Friday, February 26, 1993, Ramzi Yousef and a Jordanian friend, Eyad Ismoil, drove a yellow Ryder van into Lower Manhattan, and pulled into the public parking garage beneath the World Trade Center around noon. They parked on the underground B-2 level. Yousef ignited the 20-foot fuse, and fled. Twelve minutes later, at 12:17:37 pm, the bomb exploded in the underground garage, generating an estimated pressure of 150,000 psi.The bomb opened a 30-m (98 ft) wide hole through four sublevels of concrete. The detonation velocity of this bomb was about 15,000 ft/s (4.5 km/s). Initial news reports indicated a main transformer may have blown, not realizing a bomb had exploded in the basement.

The bomb instantly cut off the World Trade Center’s main electrical power line, knocking out the emergency lighting system. The bomb caused smoke to rise up to the 93rd floor of both towers, including through the stairwells which were not pressurized.With thick smoke filling the stairwells, evacuation was difficult for building occupants and led to many smoke inhalation injuries. Hundreds were trapped in elevators in the towers when the power was cut, including a group of 17 kindergartners, on their way down from the South Tower observation deck, who were trapped between the 35th and 36th floors for five hours.

Also as a result of the loss of power most of New York City’s radio and television stations lost their over-the-air broadcast signal for almost a week, with television stations only being able to broadcast via cable and satellite via a microwave hookup between the stations and three of the New York area’s largest cable companies, Cablevision, Comcast, and Time Warner Cable. Telephone service for much of Lower Manhattan was also disrupted.

All together, six people were killed and 1,042 others injured, most during the evacuation that followed the blast. A report from the US Fire Administration states that “Among the scores of people who fled to the roofs of the towers, 28 with medical problems were airlifted by New York City police helicopters (…)“. It is known that 15 people received traumatic injury from the blast and 20 complained of cardiac problems. One firefighter was hospitalized, while 87 others, 35 police officers, and an EMS worker were also injured in dealing with the fires and other aftermath.

The plan was that if the bomb truck was parked at the right place, the North Tower would fall onto the South Tower, collapsing them both. However, the tower did not collapse, according to Yousef’s plan, but the garage was severely damaged in the explosion. Nevertheless, had the van been parked closer to the WTC’s poured concrete foundations, Yousef’s plan might have succeeded.He escaped to Pakistan several hours after the bombing.

Due to the time at which Yousef left Jersey City, questions linger as to why he waited until noon to attack when the parking area was much less crowded.Conspirator Mahmud Abouhalima later stated that the original plan was to attack the United Nations headquarters earlier in the morning. Author Simon Reeve theorized that something went wrong, such as Yousef encountering too much security, and the target was changed to be the World Trade Center.

Bomb characteristics

Yousef was assisted by Iraqi bomb maker Abdul Rahman Yasin, who helped assemble the complex 1,310-pound (590 kg) bomb, which was made of a urea nitrate main charge with aluminum, magnesium and ferric oxide particles surrounding the explosive. The charge used nitroglycerine, ammonium nitrate dynamite, smokeless powder and fuse as booster explosives.Three tanks of bottled hydrogen were also placed in a circular configuration around the main charge, to enhance the fireball and afterburn of the solid metal particles.The use of compressed gas cylinders in this type of attack closely resembles the 1983 Beirut barracks bombing 10 years earlier. Both of these attacks used compressed gas cylinders to create fuel-air and thermobaric bombs[18] that release more energy than conventional high explosives. According to testimony in the bomb trial, only once before the 1993 attack had the FBI recorded a bomb that used urea nitrate.

The Ryder van used in the bombing had 295 cubic feet (8.4 m3) of space, which would hold up to 2,000 pounds (910 kg) of explosives. However, the van was not filled to capacity. Yousef used four 20 ft (6 m) long fuses, all covered in surgical tubing. Yasin calculated that the fuse would trigger the bomb in twelve minutes after he had used a cigarette lighter to light the fuse.

Yousef wanted the smoke to remain in the tower, therefore catching the public eye by smothering people inside, killing them slowly. He anticipated Tower One collapsing onto Tower Two after the blast.

There remains a popular belief that there was cyanide in the bomb, which is reinforced by Judge Duffy’s statement at sentencing, “You had sodium cyanide around, and I’m sure it was in the bomb.” However, the bomb’s true composition was not able to be ascertained from the crime scene and Robert Blitzer, a senior FBI official who worked on the case, stated that there was “no forensic evidence indicating the presence of sodium cyanide at the bomb site.” Furthermore, Yousef is said only to have considered adding cyanide to the bomb, and to have regretted not doing so in Peter Lance’s book 1000 Years for Revenge.

Investigation

Though the cause of the blast was not immediately known, with some suspecting a transformer explosion, agents and bomb technicians from the ATF, FBI, and the NYPD quickly responded to the scene. The magnitude of the explosion was far beyond that of a transformer explosion.

In the days after the bombing, investigators surveyed the damage and looked for clues. While combing through the rubble in the underground parking area, a bomb technician located some internal component fragments from the vehicle that delivered the bomb. A vehicle identification number (VIN), found on a piece from an axle, gave investigators crucial information that led them to a Ryder truck rental outlet in Jersey City. Investigators determined that the vehicle had been rented by Mohammad Salameh, one of Yousef’s co-conspirators.Salameh had reported the van stolen, and when he returned on March 4, 1993, to get his deposit back, authorities arrested him.

Salameh’s arrest led police to the apartment of Abdul Rahman Yasin in Jersey City, New Jersey, which Yasin was sharing with his mother, in the same building as Ramzi Yousef’s apartment. Yasin was taken to the FBI’s Newark field office in Newark, New Jersey, and was then released. The next day, he flew back to Iraq, via Amman, Jordan. Yasin was later indicted for the attack, and in 2001 he was placed on the initial list of the FBI Most Wanted Terrorists, on which he remains today. He disappeared before the U.S. coalition invasion, Operation Iraqi Freedom, in 2003. In March 1994, Salameh, Nidal Ayyad, Mahmud Abouhalima and Ahmad Ajaj were each convicted in the World Trade Center bombing. In May 1994, they were sentenced to life imprisonment.

The capture of Salameh and Yasin led authorities to Ramzi Yousef’s apartment, where they found bomb-making materials and a business card from Mohammed Jamal Khalifa. Khalifa was arrested on December 14, 1994, and was deported to Jordan by the INS on May 5, 1995. He was acquitted by a Jordanian court and lived as a free man in Saudi Arabia until his death in 2007. In 2002, it was made public that Yasin, the only person involving in the bombing who was never caught by US authorities,was being held as a prisoner on the outskirts of Baghdad, Iraq since 1994. When journalist Leslie Stahl interviewed him there for a segment on 60 Minutes on May 23, 2002 Yasin appeared in prison pajamas and handcuffs.[23] Yasin has not been heard from since the interview.