PITTSBURGH -- A district attorney will determine whether Pittsburgh police were right to kill an armed man in his Point Breeze apartment after a 10-hour standoff.

Pittsburgh police said SWAT tried to end the standoff peacefully, but Lamar Smith, 29, made aggressive moves toward an officer, causing the officer to shoot him in the chest.

"He agreed several times to surrender. He, at one point, agreed to surrender," said assistant police chief William Bochter. "At the last minute, he changed his mind."

Police said Smith, a construction worker and father of two, barricaded himself inside the apartment building in the 200 block of North Homewood Avenue at about 3 a.m. following a domestic situation between his girlfriend, her father and himself.

Police took cover when they saw Smith in his underwear with a gun in each hand.

During negotiations, police said Smith threatened he would not to be taken alive and would shoot SWAT officers.

Authorities turned off utilities to the building and used tear gas grenades in efforts to end the standoff, and entered the apartment when this failed.

Utilizing a remote camera, SWAT officers said they saw Smith lying on the floor with firearms in both hands.

Officers tried to convince him to surrender. Instead they said he stood up with firearms in both his hands and started walking toward the officers.

A marksmen saw this and fired one shot, hitting Smith in the upper torso.

"That entry was not with the intent to do harm to the suspect but with the intent to find out his location in the apartment" said Bochter.

Two SWAT officers have been placed on administrative leave.

Family members were on the scene. They said they tried to get him a lawyer to get Smith out.

"He just said he was in a real tough situation," said a man who identified himself as Smith's brother. "I told him to think about his family and his daughter."

A local attorney contacted by the family reportedly showed up at the scene but was not allowed to talk to the man inside.

Relatives can't understand what would set their family member off.

"He's a great guy. He does for his kids. He's always helping other people. That's just the type of guy he is," said one family member.

All residents of the apartment building were evacuated and put on a bus in order to keep warm.

"Police came knocking on the door, evacuating our building," said apartment resident Tony Brown. "They said something about some dude up there with a gun, holding them off."