Five dead, including shooter, in Tennessee attacks
田纳西州发生枪击案

WASHINGTON, July 16 (Xinhua) -- Shootings at two military facilities in Chattanooga, Tennessee, left four U.S. marines dead and three others wounded Thursday. The gunman was also killed later, authorities said.

According to local police, the two shooting incidents, which lasted for about 30 minutes, happened around 11:00 a.m., local time, at a military recruiting center and the Naval Reserve Center about 10 kilometers apart. The shooter reportedly shot while driving in an open-top Mustang.

The Federal Bureau of Investigation (FBI) had already identified the suspect as 24-year-old Muhammad Youssef Abdulazeez. U.S. President Barack Obama said a full investigation was under way with the FBI in the lead.

"We've also been in contact with the Department of Defense to make sure that all our Defense facilities are properly attentive and vigilant as we sort through exactly what happened," said Obama in a statement, adding that initial investigation showed that the gunman acted alone.

Earlier Thursday the FBI said it had already started its investigation into what local officials described as "an act of domestic terrorism."

"We will treat this as a terrorism investigation until we determine it was not," said Ed Reinhold, an FBI special agent in charge of the investigation, at a press conference. "We have not determined if it was an act of terrorism or a criminal act."

Meanwhile, Reinhold said that the gunman, with "numerous weapons" on him, did not work at the military facilities involved.

The shooting incidents came one month after a racially motivated white gunman shot dead nine African-American churchgoers in Charleston, South Carolina. The authorities were initially investigating the Charleston church massacre as "hate crime," rather than a possible act of terrorism.

Thursday's shootings also came at a time when U.S. military and law enforcement officials were increasingly concerned about threats posed by domestic sympathizers of the extremist group the Islamic State. The group had earlier called on its supporters to carry out lone-wolf attacks against "its enemies" worldwide during the month of Ramadan.

The Washington Post earlier quoted senior FBI officials as saying that the shooting did not appear to be related to any terrorist group.