After a day of searching, authorities had few leads and only a sketchy description Friday of a robber who shot and killed two armored car guards at a bank ATM.

Police were still trying to determine how much money the man got away with when he approached the guards Thursday morning as they were picking up deposits and fired without saying a word.

"He just came out initially and just assassinated them, that fast," police Commissioner Sylvester Johnson said.

The robber approached the car from behind shortly after 8 a.m., shot one guard in the chest, then went around the vehicle and shot another as he tried to unholster his gun, police said. A third guard was slightly injured by flying glass.

Johnson said none of the guards fired a shot.

Police declined to discuss the search Friday, except to say that it was ongoing.

Investigators also were trying to determine how much money the robber got away with. They believe he may have grabbed deposits — likely a mix of checks and cash, police said.

Johnson said surveillance tapes from the Wachovia bank's security camera and another nearby business showed the robber getting out of his car and putting on gloves before killing the two.

William Widmaier, 65, was shot once in the chest, and Joseph Alullo, 54, was shot three times in the chest and abdomen, police said.

Police released cropped still frames from the bank surveillance tape that show a man wearing a yellow baseball cap and bright yellow or orange gloves pointing a handgun toward the front of the ATM. FBI spokeswoman Jerri Williams said the full view of the scene was being withheld out of respect for the victims' families.

The photos did not clearly show the robber's face. Authorities said he was a black man in his early to mid-20s, with a beard. His getaway car was described as a dark 2007 or 2008 Acura TL Type-S.

Widmaier, a Philadelphia police officer from 1966 to 1989, and Alullo, who served on the police force from 1973 to 2000, were assigned to the same district, where they became friends, Johnson said.

The third guard, whose name was not released, was grazed by shattered glass as the robber tried to shoot through the armored car, Loomis spokesman Mark Clark said. He was treated at a hospital for lacerations.

Loomis has about 190 employees in Philadelphia, about half of them guards. "People are feeling a mix of sadness at the loss of teammates, a little bit of anger, and probably some fear," Clark said.

The company encourages guards to obtain bullet-proof vests and pays part of their costs, but does not require them now, Clark said Friday.

"At this point, when we have an incident like this, we look at what happened, what could we have done differently," he said. "One of the things that we're re-evaluating is the vest policy."

Widmaier, married with adult children, was the union shop steward for the Pennsauken, N.J., based division of Loomis, where the men worked. Alullo was married with three daughters, Loomis said in a news release.