Michael Anthony Salters, described by law enforcement officials as a drug dealer and mediator among competing District drug organizations, was shot and killed late Tuesday near First and Bryant streets NW when an unidentified gunman opened fire on Salters's car, D.C. police reported.

Salters's body, still inside his bullet-riddled car, was left outside the entrance to Washington Hospital Center shortly after 10:30 p.m. Tuesday, said 5th District Capt. James Coffey.

Salters was pronounced dead about 1 a.m. yesterday, said Officer Daniel Straub, a D.C. police spokesman. The police department released few details of the incident yesterday. Sources said Salters had been shot at least six times.

Law enforcement sources said Salters was one of the city's largest drug dealers but that his real power was in his ability to referee turf disputes among rival drug dealers.

A law enforcement source said Salters had been implicated in drug deals of more than 200 pounds, but that he had proved too "well insulated" from direct involvement to be charged. Agents at times put Salters under intense surveillance, and interviewed drug dealers who said they had worked with and for him, law enforcement sources said. His name also came up in wiretapped conversations, they said.

Federal drug officials say they have been told by several drug dealers that some dealers ceded to Salters the power to assign drug territories for PCP, heroin, cocaine and other drugs.

In a pretrial hearing in the cocaine distribution case of drug gang leader Rayful Edmond III, Salters was identified as the person who in August 1988 imposed a cease-fire in the bloody warfare between Edmond's organization and a breakaway faction operating in the Trinidad section of Northeast Washington.

Drug Enforcement Administration agent John Cornille testified that Salters met with the two rival groups and told them to stop killing one another because it was bringing increased police pressure and cutting into drug profits in the city. A law enforcement source said that after the meeting the killings stopped.

Salters was not charged in the Edmond case, but federal sources said he pooled money with Edmond and partner Tony Lewis to buy cocaine from the Los Angeles drug broker who was Edmond's pipeline to Colombian dealers.

Salters was also allied with a drug gang headed by Eddie Mathis, now serving a 15-year sentence on gun charges. The gang was involved last year in a bloody battle with a rival gang for control of drug sales in far Southeast Washington.

On Tuesday night a relative of Salters's was driving a van behind Salters's car east on Bryant when he was cut off by another car near First, police said. An occupant of the vehicle that cut off the van then opened fire on Salters, the sources said. An uninjured passenger in Salters's car then drove to the hospital, sources said.

Police listed a Fort Washington address for Salters, who federal authorities believed had several residences in the area. When arrested last year in Montgomery County on a variety of charges, Salters listed his address as in the 5100 block of Seventh Street NW.

In October, Salters was convicted in that case of carrying a handgun and resisting arrest, and sentenced to one year of probation. The charges stemmed from an April 1990 incident in which county police stopped a car in which Salters was a passenger. Police said Salters tried to flee after a police officer frisking him found a bulge in his pocket.

Law enforcement sources said Salters's main drug operations were along Kennedy Street NW, stretching at times from North Capitol Street to Georgia Avenue.

A law enforcement source said last night that Salters's killing may have been related to a fatal shooting hours earlier on Seventh Street between O and P streets NW. The victim's identity has not been released by police.