(AP) –  The death toll in the Chattanooga shootings includes four U.S. Marines and the sole gunman believed responsible, a U.S. official told The Associated Press, speaking on condition of anonymity to discuss an ongoing investigation.

The official said two others, a soldier and a police officer, were wounded.

A U.S. attorney says the killing of four people during a shooting rampage in Chattanooga is an “act of domestic terrorism.”

U.S. Attorney Bill Killian made the comments Thursday during a news conference. Mayor Andy Berke says two different military sites were “viciously attacked.” The shooter was killed at a Naval reserve center, where the victims were also slain.

There was also a shooting at a military recruitment center about 7 miles away.

A woman who says she witnessed the shooting in Chattanooga says she heard a barrage of gunfire near one of the shooting sites.

“It was rapid fire, like pow pow pow pow, so quickly. The next thing I knew there were police cars coming from every direction,” said Marilyn Hutcheson, who works at a Binswanger Glass.

Hutcheson says she ran inside, where she remains with other employees and a customer. The gunfire continued with occasional bursts she estimated for 20 minutes.

“We’re apprehensive,” Hutcheson said. “Not knowing what transpired, if it was a grievance or terroristic related, we just don’t know.”

President Barack Obama has been briefed by his national security team on the shooting involving two military sites in Tennessee.

White House spokesman Eric Schultz says that the president will continue getting updates from his staff as needed.

Obama was in Oklahoma to speak about criminal justice reform at a federal prison at the time of the shooting. He plans to return to Washington on Thursday afternoon.