There is no curb service for cocaine buyers at Montana Terrace, the run-down public housing project in Northeast Washington where, sources have told police, basketball star Len Bias may have gone hours before his death Thursday morning.

The youthful dealers hang back from the street in the shadow of a low-slung recreation building. A heavy dose of police attention to their illegal business in the past few months has made them wary of strangers.

But still the cars arrive with District, Maryland and Virginia tags, and the customers walk up the grassless hill to make their purchases. Late Friday night business was off, as teams of uniformed police officers walked through the apartment and town house complex during a routine sweep, disrupting the crowds of young people.

"That is one nasty little place," said one officer.

The sprawling complex is on the west side of Montana Avenue between New York and Rhode Island avenues NE. It adjoins another large housing project called Brentwood Village.

According to sources close to the investigation, police have received statements that Bias and a friend, Brian Tribble, drove to the District near Montana and New York avenues NE early Thursday. Bias collapsed with a cardiac arrest at his dormitory about 6:30 a.m.

"The business started there to serve that community, and now they have customers coming in from outside the area," said Capt. James Nestor, head of the police department's narcotics branch. "That is a large area, and it is easy for the dealers to hide there. They don't stand out like they would if they stood on the usual street corner."

A narcotics officer said police have trouble making arrests at Montana Terrace because it is on a hill, allowing lookouts to spot the officers long before they arrive. The dealers know the terrain intimately, the officer said, and in the event of a chase they always seem to be able to duck into buildings and find sanctuary.

"We go up there pretty strong and pretty deep," he said. "We always take lots of officers. That is not a place you want to go alone as a police officer."