Four Marines killed in attack at military sites

Four Marines killed in attack at military sites

Mohammad Youssuf Abdulazeez was carrying 30-round magazines when he opened fire, according to a source briefed by law enforcement. Abdulazeez kept police at bay for some time with the amount of ammunition he had, according to the source.

The shooting suspect was armed with an AK-47 style weapon? at the time of the attack according to two law enforcement officials briefed on the investigation.

[Previous story, posted at 10:30 p.m. ET Thursday]

Who was the gunman accused of killing four Marines in a shooting rampage Thursday at two military centers in Chattanooga, Tennessee, and why did he open fire?

Suspected shooter Mohammad Youssuf Abdulazeez, 24, is dead, the FBI said. But -- publicly, at least -- investigators haven't said much more about him.

Witnesses saw Abdulazeez spray a hail of bullets at the glass doors of a military recruiting center in a strip mall. Then the gunman, who according to a law enforcement official was driving in a rented silver Ford Mustang convertible, moved on to his next target more than seven miles away: a Naval reserve center. There, he rammed into a gate at some point during his shooting rampage and was eventually killed by police, a U.S. official said.

Now, with the FBI in the lead, a terrorism task force is investigating, a law enforcement source said.