The FBI identified the deceased gunman in the Thursday attack on military personnel in Chattanooga, Tennessee, as 24-year-old Muhammad Youssef Abdulazeez.

He was believed to have been born in Kuwait, and it was unclear whether he was a U.S. or Kuwaiti citizen. The official was speaking on condition of anonymity to discuss the ongoing, sensitive investigation. It was not immediately clear whether the gunman’s first name was spelled Muhammad or Mohammad.

He is from Hixson, Tennessee, which is just a few miles across the river from Chattanooga.

Booking records indicate an individual with the same name and age was previously arrested in the area earlier this year for DUI and other driving-related offenses.

The yearbook quote provided by Abdulazeez to his high-school year book created a stir on social media. “My name causes national security alerts. What does yours do?” the provided quote said.

Abdulazeez was also an MMA fighter and video of his fights are available online.

Authorities and officials say the gunman killed four Marines and wounded a police officer and others in two attacks on military facilities. The gunman was also dead.

The Associated Press contributed to this report. This story has been updated with new information. Last update: 8:02 p.m. ET.

Follow the author of this story on Twitter and Facebook: