President Obama called for all flags at the White House and all federal buildings, including overseas embassies, to be lowered to half-staff to honor the five troops killed in a  shooting rampage at a Chattanooga, Tenn., reserve center.

The move, which comes four days after the killings, follows growing calls and criticism from conservatives and some veterans groups calling on the president to honor the men. The White House issued the president's order a few minutes after Obama finished a speech at a Veterans of Foreign Wars convention in Pittsburgh on Tuesday. "Our thoughts and prayers as a Nation are with the service members killed this week in Chattanooga," Obama said in a statement.

In his most extended remarks about the Chattanooga  shootings, Obama on Tuesday praised the four Marines and the sailor “killed so senselessly in Chattanooga.”

He read out their names one by one, recounting some highlights of their personal lives, their pride in wearing the uniform and their service overseas. He described how Marine Gunnery Sgt. Thomas J. Sullivan had charged the gunman, trying to protect his troops when the shooting began.

“Our nation endures because people like you put on the uniform and help keep this nation free,” he said in his VFW speech.

Obama announced his decision to lower the flags shortly after House Speaker John A. Boehner (R-Ohio) and Senate Majority Leader Mitch McConnell (R-Ky.) ordered flags at the Capitol lowered.

Pro-gun groups have called in recent days for Obama to reverse rules, instituted during the Clinton administration and backed by the Pentagon's brass, that prohibit military recruiters from carrying firearms.  Marcus Luttrell, a former Navy SEAL who wrote the best-selling book “Lone Survivor” about his experiences in Afghanistan, was among those calling for arming recruiters. He also ripped the military's decision to have recruiters in the vicinity of Chattanooga temporarily come to work in civilian clothes.

"That's not how we respond in the military when we get hit, we don't take off our uniforms, drop our weps and run," Luttrell wrote in the Facebook post.