A blast caused by what the FBI called "an improvised explosive device" rocked a Bloomington Islamic center before dawn Saturday, just as a small group of Muslim worshipers had gathered for the day's first round of prayers.
No one was hurt in the explosion, which heavily damaged an imam's office at the Dar Al Farooq Center and sent smoke wafting through the large building. Windows in the office were shattered, either by the blast or by an object thrown through them.
The blast was reported at 5:05 a.m. as about a dozen people gathered in a room nearby for morning prayers and jolted awake many residents of the neighborhood. Congregants and neighbors expressed relief that there were no injuries, but also reacted with shock and dismay.
When police arrived, they found smoke and fire damage to the building, said Bloomington Police Chief Jeff Potts. Agents from the FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives soon joined the investigation. A large area outside the center was taped off as investigators, including members of the FBI's Joint Terrorism Task Force, combed through the grass.
At an early evening news conference, Special Agent in Charge Richard Thornton said an "improvised explosive device" caused the blast, but that investigators still must determine "who and why."
"The post-blast environment is very detailed," he said. "You search the wide area in an attempt to find as many components as you can of the device to help us understand how the device was made. That process is substantially complete. … It was an improvised explosive device that was set off early this morning."
Witnesses have been interviewed, evidence has been sent to various labs, and video and cellphone data are being analyzed, he said. He asked that anyone with information contact 1-800-CALL-FBI.
The U.S. Department of Homeland Security issued a news release saying that acting DHS Secretary Elaine Duke was aware of the explosion and was "in close contact with federal, state and local authorities and local community leaders as the investigation into this matter continues."