The police have arrested four Harlem teenagers and charged them with the robbery and murder of a New York University student who died earlier this month after he was chased onto 125th Street and hit by a car.

The effort has produced results: last month, for example, the police identified Jonathan Williams, a man held at Rikers Island on a murder charge, as the prime suspect in the 1998 rape of a Harlem teenager.

Mr. Reyes maintained that the five Harlem teenagers convicted of the attack had nothing to do with it.

He planned to build the fence in two years, with the help of 10 Harlem teenagers.

His second book, "The Children of Ham," published in 1976, told the story of a group of Harlem teenagers who escape from the influence of heroin.

In the jogger case, the Manhattan district attorney's office is near the end of an exhaustive inquiry into Mr. Reyes's claim that the five Harlem teenagers convicted of the crime had nothing to do with it.

Four Harlem teenagers accused of killing a New York University student by chasing him into a car's path during a robbery attempt will be tried as juveniles rather than adults, the Manhattan district attorney's office said yesterday.

The police have arrested a Harlem teenager on charges that he fatally shot a 16-year-old girl and wounded three young men late Thursday afternoon, the authorities said.

The police arrested a Harlem teenager yesterday and charged him with manslaughter in the death of a youth who fell and hit his head during a fistfight on Monday night.

Prosecutors reconsidering whether Harlem teenagers beat and raped a female jogger during a Central Park rampage 13 years ago are also debating whether the teenagers' convictions for other crimes that night should be thrown out, officials said.