PHILADELPHIA » Philadelphia police are mourning the death of an officer who was shot in the head and killed after he and his partner exchanged gunfire with two suspects trying to rob a video game store.

Police said Thursday the slain officer, Robert Wilson III, fired back even as he was being shot by suspects on either side of him. One was struck and taken to a hospital while the other was in custody.

"The entire department is in shock and is in mourning," said Philadelphia Police Commissioner Charles Ramsey at an evening news conference.

Ramsey, red-eyed, said he had met the 30-year-old Wilson and his partner when they took part in a recent pilot program in which officers wore body cameras.

"I knew him, had met him. He was one of the best police officers this city has to offer, period," Ramsey said, standing beside the mayor, the district attorney and other city officials.

It was not immediately clear if Wilson was wearing a body camera when he was shot at 4:44 p.m. Thursday, but authorities did seize video from store security cameras. He was shot multiple times. He was pronounced dead at 6:25 p.m. at Temple University Hospital.

Wilson was inside a GameStop, located in a north Philadelphia strip mall, when the two suspects entered and announced a robbery, Ramsey said. The partner also exchanged gunfire with the suspects, but was not shot. Both suspects have prior records, Ramsey said.

It wasn’t clear who shot the suspect. Police believe they were armed with two guns.

Wilson was an eight-year veteran of the department. His survivors include a 9-year-old son and 1-year-old child, Ramsey said.

"This 9-year-old is going to grow up without a father because of what happened today," Ramsey said. "This 1-year-old is going to grow up without a dad."

A police procession escorted an ambulance that transported Wilson’s body to the Medical Examiner’s Office Thursday night.

"Please keep his family in your prayers," the Philadelphia Police Department asked on its Twitter page, and nearly five dozen residents, political officials and police departments from around the country responded with their condolences.

"Our thoughts are with the officer," said Joey Mooring, director of public relations at the Texas-based GameStop.

"This senseless act is devastating and a stark reminder of the danger faced everyday by our brave men and women in uniform," Gov. Tom Wolf said in a statement.

The last city officer killed, 40-year-old Moses Walker Jr., was fatally shot in an attempted robbery as he walked to a bus stop after an overnight shift in August 2012. His assailant was convicted of first-degree murder in December in a nonjury trial that spared a possible death sentence.