Muhammad Youssef Abdulazeez: 5 Fast Facts You Need to Know  —  Muhammad Youssef Abdulazeez, left, opened fire at two military facilities in Chattanooga, Tennessee, killing four Marines and wounding three others before he was killed.  At right is the recruiting center's front door, which was pierced by bullets.

4 Marines killed, police officer shot in Chattanooga  —  UPDATE: Four U.S. marines were killed Thursday by a gunman in Chattanooga.  Mayor Andy Berke confirmed the fatalities in an afternoon news conference.  A police officer, who was wounded, is said to be in stable condition.

This story is developing. … The gunman in the Chattanooga military installation shooting has been identified 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.

This breaking news story is being continually updated as new information comes in. … Four members of the military were killed in two attacks on military centers in separate parts of Chattanooga by an unknown gunman, leading to lockdowns at local hospitals as well as the Army Recruiting Center …

FBI Statement on Shootings at Military Facilities in Chattanooga, Tennessee … The FBI's Knoxville Field Office, along with the Chattanooga Police Department and other law enforcement partners, are working jointly to investigate today's shootings at a military recruitment center and a reserve center …

Four Marines Killed in Chattanooga Shootings  —  CHATTANOOGA, Tenn. — A gunman opened fire on a Navy and Marine Reserve Center in Chattanooga, Tenn., on Thursday, leaving four Marines dead, and a recruiter wounded.  The gunman was also killed.  —  Officials said during a news conference …

First Read: How Donald Trump Shrank the GOP Field  —  First Read is a morning briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.  —  How Donald Trump shrank the GOP field  —  Yes, 17 Republicans are running for president.