(CNN) — Four Marines were killed Thursday when a gunman attacked two military centers in Chattanooga, Tennessee.
Police killed the suspected shooter, 24-year-old Mohammod Youssuf Abdulazeez, who rammed a gate at a Navy reserve center with his car during the shooting rampage, a U.S. official said.
“I have directed the FBI to take the lead in the national security investigation of this heinous attack on members of our military,” U.S. Attorney General Loretta Lynch said, calling the shooting “a shameful and cowardly act of violence.”
A terrorism task force involving federal and local agencies is investigating, a law enforcement source said.
Authorities “have not determined whether it was an act of terrorism or whether it was a criminal act,” Ed Reinhold, FBI special agent in charge, told reporters. “We are looking at every possible avenue, whether it was terrorism — whether it was domestic, international — or whether it was a simple, criminal act.”
A key detail will help them make that determination: finding out the suspect’s motive.
Who was the suspect?
Authorities have released few details about the alleged gunman, but some details have begun to emerge about his past.
Abdulazeez was born in Kuwait and had Jordanian citizenship, two law enforcement officials said. He was a naturalized U.S. citizen, one official said.
He graduated from the University of Tennessee at Chattanooga in 2012 with a degree in electrical engineering, university spokesman Chuck Cantrell said.
In the neighborhood where Abdulazeez is believed to have lived, police cars and an ambulance were on the streets. Residents were blocked from reaching their homes. A woman was escorted in handcuffs from the area, but it was unclear whether she was connected to the alleged gunman.
“We will treat this as a terrorism investigation until it can be determined that it is not,” Reinhold said. U.S. Attorney Bill Killian earlier told reporters that authorities were treating the shooting as an “act of domestic terrorism.”
Abdulazeez was not in any of U.S. databases of suspected terrorists, a U.S. official said.
Kevin Emily, his former high school wrestling coach, described him as “a great student” who sometimes missed practice to pray.
“He always contributed, always did what I asked him to do. I never had any problems out of Mohammod,” Emily told CNN’s “Erin Burnett: Outfront.” “He was very humble when he was in high school. He’d always listen to me, looked me in the eye. He was just — in high school he was a great kid.”
Scott Schraeder, Abdulazeez’s former mixed martial arts coach, described him as “all-American.”
“Never loud, never boisterous, never out of line, hard worker, seemed to enjoy the training, got along with everybody.”
Injured sailor in ‘serious condition’
The shootings unfolded at two sites over 30 minutes, Reinhold said.
The suspected gunman started spraying bullets at the glass doors of a strip mall military recruiting center around 10:45 a.m. ET, witnesses said. From there, he headed to another location more than seven miles away, an operational support center operated by the U.S. Navy. That’s where the four victims and the gunman were killed, Reinhold said.
At least three people were injured: a police officer, a Marine Corps recruiter and a sailor.
The police officer, who was injured when he was shot in the ankle, was treated at the hospital, Chattanooga Mayor Andy Berke said. Officer Dennis Pedigo was one of the first responders on the scene, a law enforcement source close to the investigation said.
The recruiter, who was wounded in the leg, was treated and released from the hospital, the U.S. Marines said.
A female sailor who was shot is in surgery and in “pretty serious condition,” a Pentagon official told CNN’s Barbara Starr.
What was security situation?
The shooting left the city reeling and raised questions about the security at the military centers.
“Today was a nightmare for the city of Chattanooga. … We had someone viciously attack, at two different locations, people who proudly serve our country,” Berke said.
Authorities haven’t released details yet about where at the centers the victims were shot or how the gunman gained access.
U.S. President Barack Obama said the FBI director had briefed him on the shootings.
“We take all shootings very seriously. Obviously when you have an attack on a U.S. military facility, then we have to make sure that we have all the information necessary to make an assessment in terms of how this attack took place and what further precautions we can take in the future,” he said, vowing that the investigation would be “thorough and prompt.”
Homeland Security Secretary Jeh Johnson said authorities were stepping up security at “certain federal facilities, out of an abundance of caution” after the shootings.
‘It was very loud and very fast’
April Grimmett said she was working at a hair salon near the recruiting center when she looked out a window and saw a man ducking in between cars.
“Shortly after that, we heard the (shots). It was very loud and very fast,” she said.
A photo that she took shows glass doors damaged by the gunfire.
“I could not believe how many bullet holes were in that door. It was insane,” she said.
Gina Mule, a server at a restaurant, said she saw a man who’d been in a silver convertible Mustang, firing a “high-powered rifle” at the recruiting offices at about 10:50 a.m.
She said she first heard “Pow, pow, pow!” She then went to a window, through which she said she saw the man firing shots.
“He never got out of the car,” she said. “He had a big, huge, high-powered rifle, and he was unloading shots right into the recruiters.”
CNN’s Danelle Garcia, Drew Griffin, Gary Tuchman, Brian Todd, Joshua Gaynor, Pamela Brown, Barbara Starr, Paul Vercammen, Millicent Smith, Stephanie Gallman, Evan Perez, Shimon Prokupecz, Devon Sayers, Ashley Fantz and Victor Blackwell contributed to this report.
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