The father and son were shot and killed three blocks and 15 years apart, in a section of Philadelphia they call Nicetown.

Officer Dave Williams of the 39th Police District responded to both bloody scenes.

In the first, Lamonte Moore was among several gunned down in a 1991 melee at a bar. "It woke me up. I had never seen a massacre like that," Williams says.

Then, on the afternoon of July 6, Williams tended to Moore's son, Jarrett Gore - now a teenager who loved basketball and buffalo wings - as he lay dying in the street at 16th and Erie.

"At first, I thought it was another kid from the neighborhood," Williams, 39, says. "Then I rolled him over and saw it was Jarrett. He looked at me and then he rolled his eyes in the back of his head. That's when I started screaming, 'Come back! Don't leave me!' because I thought he was giving up."

Williams, whose school beat covers Simon Gratz, says, "Me and Jarrett talked almost every day."

"Some kids will let you talk to them, let you inside," he explains. "Jarrett let me in."

Jarrett and classmate Tristan Williamson were meeting to continue a dispute. Witnesses say Jarrett, unarmed, was preparing for a fistfight when Tristan shot him in the neck and stomach.

"I love 'em both," says Williams, without hesitation. The cop, who calls himself "a dad in a police uniform" and has three children of his own, tries to mediate arguments in a neighborhood where, he says, kids put "the fancy guys, the drug dealers," on pedestals.

After Jarrett's death, Williams chastised a group of older teens he believes influenced Tristan, telling them, " 'You guys are making monsters.'... They said, 'It's not our fault. We didn't put a gun in his hand.' "

Even at Jarrett's funeral yesterday, he was working to calm mourners looking to place blame for the tragedy and spoiling for a fight.

"I think I've been doing a hell of a job," Williams says, "but I don't know."