It's a neighborhood so notoriously crime-riddled that police parked a marked trailer curbside at 23rd and Tasker streets to intimidate thugs and ease surveillance efforts.

So maybe it's no surprise that a thug reached for his gun, shouting that he was ready to shoot, when a uniformed police officer came there late Wednesday.

The threat ended fatally for the thug, who ignored the officer's repeated orders to surrender his weapon. The officer shot the man once in the chest as he reached into his waistband, said Lt. Frank Vanore. The man, who died 20 minutes later at the Hospital of the University of Pennsylvania, remained unidentified yesterday.

At the scene, investigators found the man's weapon, a replica pellet gun, Vanore said.

He was the 11th civilian killed by police this year, compared with 15 at this point last year, Vanore said.

"The last thing an officer wants to do is use deadly force, but sometimes he is forced to do that to protect himself and the public," Vanore said. "This was a brazen act, and it was a split-second decision that unfortunately in this case was fatal."

The incident started at 11:20 p.m., when two men emerged, arguing, from Lid's Cafe Society, a two-story, yellow-stucco bar at 23rd and Tasker, Vanore said.

The argument arose when a man came to the defense of a woman who was trying unsuccessfully to rebuff another man's pickup attempt, said Sgt. William Gallagher of the homicide unit.

The men walked past a parked police cruiser, arguing, until one called to the officer for assistance, Vanore said. The second man yelled that he would shoot the officer and reached toward his waistband, ignoring the officer's commands to stop, Vanore said.

"He was threatening to shoot everybody," Gallagher said.

Gunfire is common in the area, which is plagued by drug activity and home to the notorious Bey family, a clan police have called urban terrorists. Hakeem Bey is serving life for a 2000 murder and is suspected in others; his uncle Dawud Bey is serving 10 years in federal prison on drug charges.

The officer, a seven-year veteran, was placed on desk duty, pending outcome of investigations by the homicide and internal-affairs units.

Outside Lid's Cafe yesterday, passersby had little sympathy for the dead man.

"He had to be crazy to draw a gun on a cop. You get what you look for," said Lawrence Walters, 66, who was waiting for a bus to visit a friend.

Neighbor Shawn Miller, 20, agreed: "It's a crazy neighborhood - the worst in South Philly."