Man questioned in fatal armed robbery

(CNN) -- Philadelphia police were questioning a man Friday about the shooting deaths of two armed guards Thursday during an armored car robbery.

The unidentified man had been arrested for an unrelated crime, police commissioner Sylvester Johnson said.

"We are not saying that he is connected, we are not saying that he is not connected," Johnson told reporters.

"At this point it is too early to tell. We are just looking into him at this point. He has not been arrested [for the robbery]. We are not giving any names, any information or anything other than that."

The dead guards were identified as retired police officers Joseph Allullo, 50, and William Widmaier, 65. Each had more than 20 years on the force. Allullo retired in 2003 and Widmaier retired in 1999.

A third guard was wounded in the robbery.

The lone gunman took an undetermined amount of money, police said. Police said they were searching for a black man who was wearing a black shirt, blue jeans and a yellow cap. He fled the scene in a black Acura TL with tinted windows and a sunroof, police said.

The guards were attacked shortly after 8 a.m. as they were servicing an ATM outside a Wachovia Bank branch near Roosevelt Mall in northeast Philadelphia, police said. The gunman fired at two guards who were outside their vehicle and at the third guard who was inside the vehicle. Watch video images of the gunman at the scene »

The third guard was hurt by flying glass when a bullet shattered one of the vehicle's windows, said Mark Clark, a spokesman for Loomis, the company that owns the armored car.

Police said they found an empty black duffel bag behind an off-track betting parlor near the scene of the crime that may have been taken from the armored car after the shootings.

Several elementary schools in the area were briefly locked down after the incident. The nearby Roosevelt Mall was also shut.

The bank branch is located near entrances to I-95 and I-76, either of which, police said, could have served as an escape route.

Police were reviewing security tapes from the bank's cameras. E-mail to a friend

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