According to prosecutors, the three men drove to the Pit and forced one of Rook’s friends into a car.

The kidnapping victim’s girlfiend called the Cambridge Police Department at 10:46 p.m. and gave a description of the car, Cambridge Police spokesperson Frank Pasquarello said. About 40 minutes later, he said, a CPD officer spotted the car on Mass. Ave. and opened the door to find the victim, who was alone and unharmed.

An 18-year-old Pit regular with strawberry blond hair who identified himself as “Caos” claimed to be the man who was kidnapped yesterday.

He said he suspected there had been a murder as soon as the suspects forced him into the car.

“I saw the bloody knives,” Caos said. “It wasn’t my blood, so I knew it was someone else’s.”

Pasquarello would not confirm that Caos was the kidnapping victim.

Some Pit kids yesterday said Rook’s murder is an indication that gang activity is changing the atmosphere outside the T-station.

In addition to Parker and the Vasquez brothers, Pit kids said, a group of gang members who call themselves Crips started congregating around the Pit about a year ago.

Alex, 19, described the Crips as “kids trying to be bullies,” and said they’ve changed the Pit from a peaceful haven for hippie kids to a frightening place.

“Almost no one hangs out here anymore,” she said. “They’re all scared.”