An American flag waves at site of Boston atta
An American flag waves at site of Boston atta Reuters

While the Pakistani Taliban has denied involvement in Monday's Boston marathon bombing, it has openly applauded the heinous attack, which killed three and injured over a hundred more. 

“Wherever we find Americans we will kill them, but we don’t have any connection with the Boston explosions,” Tehreek-e-Taliban Pakistan (TTP) spokesman Ihsanullah Ihsan said, according to reports.

While no one has claimed responsibility for the attack, there has been increasing speculation that the Pakistani Taliban is to blame.

The terrorist group harbored Osama bin Laden in Afghanistan until the U.S. invasion of 2001. It claimed responsibility for a botched car bombing in New York's Times Square in 2010, for which a Pakistani-American man, Faisal Shahzad, is serving a life sentence, as well as countless other attacks against American targets. 

“This was a heinous and cowardly act, and given what we now know took place, the FBI is investigating it as an act of terrorism,” President Obama said following the attack. “Any time bombs are used, it is a terrorist act.

"What we don't yet know, however, is who carried out this attack or why, whether it was planned and executed by a terrorist organization, foreign or domestic, or was the act of a malevolent individual," Obama said.

Defense Secretary Chuck Hagel told a House panel on Tuesday that the Boston bombing is a "cruel act of terror."

Hagel said that while federal officials have yet to identify any suspects, he is predicting a lengthy and "thorough" investigation into the attack.