How Long We Could Have To Wait To Know Who Was Behind The Boston Bombing

Timothy McVeigh was arrested within 90 minutes of the bombing by an Oklahoma state trooper and was charged in connection with the bombing two days later. His co-conspirator Terry Nichols was arrested on May 10.

Investigators looking through rubble in the aftermath of the bombing found a critical clue when they identified the van used in the explosion. This led them to a man who reported it stolen, Mohammad Salameh, who was quickly arrested and charged. Ramzi Yousef, one of the the other main perpetrators, was arrested in Pakistan in 1995. The other co-conspirators in the bombing were also eventually caught, with the exception of Abdul Yasin, who has not been heard from since a 2002 interview in Iraq.

It wasn't until the publication of Ted Kaczynski's "Manifesto" that federal investigators were able to pinpoint him as the source, thanks to a tip from his brother identifying his writing style.

After the media misidentified Richard Jewell as a suspect in 1996, the FBI had few leads in the bombing. That was until 1997, when a similar bomb at an abortion clinic bombing provided a link between the two bombings. The FBI identified Eric Rudolph as a suspect in 1998, and he was caught in 2003.

Within days, the United States had pinpointed Osama bin Laden as the mastermind behind the attacks and President Clinton ordered air strikes on targets within Afghanistan and Sudan.

In the hours and days following the Sept. 11 attacks, investigators were quickly able to link the 9/11 hijackers to al-Qaeda, and with it, terrorist mastermind Osama bin Laden.