The three - joined by a host of City Council members and Pennsylvania state legislators - railed against the National Rifle Association for supporting the availability of such guns. The ban expired in 2004 after 10 years.

Liczbinski "didn't stand a chance" against the Chinese-made SKS carbine that was used to kill him, Nutter said. "What is most disturbing about this incident is the nature of the weapon."

He said the carbine was powerful enough to penetrate a car and kill someone inside. The body armor worn by police cannot withstand shots from the carbine, Nutter added. Liczbinski was not wearing body armor when he was shot.

The SKS is a semiautomatic rifle, although it can be converted with simple hand tools to a fully automatic submachine gun.

It was not explicitly included in the federal ban. When questioned abut that, Ramsey responded angrily: "Then add it to the frickin' list."

Nutter and Rendell circulated a letter seeking a ban and being sent to Pennsylvania's congressional delegation.

"We are writing to urge you to stand up for our nation's law enforcement officers by reenacting legislation banning the possession, manufacture, use or importation of assault weapons," the letter states. "Passing such critical officer safety legislation will protect our police from weapons that have no other purpose than to maim and kill them."

While the ban would not have prohibited the gun that killed Liczbinski, Rendell said, the officer's murder illustrates the need for stricter control on such high-powered guns.

Assault rifles "are not used for sport, and they shouldn't be in possession of any citizen to protect themselves," Rendell said.