A 29-year-old Washington man barricaded himself for eight hours yesterday in his third-floor apartment, withstood a barrage of more than 30 teargas canisters and was not subdued until police blew open the door of the unit with an explosive device.

The man, who police said was armed with four weapons, was identified as John E. Fuller, who lived at 1350 Clifton St. NW, in the sprawling Clifton Terrace apartment complex where the day-long drama occurred.

The drama ended about 6:30 p.m. as firemen started up a ladder to a third-floor balcony to extinguish the fire caused by the explosion. When the firemen saw Fuller on the balcony, one jumped off the ladder and the others shouted for police. Two officers then scrambled up the ladder and subdued Fuller after a brief struggle on the balcony.

Authorities said they were not certain what triggered the long siege. But they did note that Fuller was facing a second-degree murder charge and apparently was concerened about his estrangement from a girl friend.A friend of Fuller's said the man Fuller is charged with killing was the son of the girl friend.

Shortly before 10:30 a.m., police said, Fuller called them and said: "I killed a boy; why don't you come get met?" But, authorities said, no other person apparently was in the apartment with Fuller at any time.

Fuller's call eventually drew scores of police and firemen to the scene, and at least 1,000 onlookers had crowded into the neighborhood at the time police finally subdued Fuller.

The first policemen who arrived at the scene moments after Fuller's call tried to negotiate with the man. Police said they heard a single gunshot from Fuller's apartment as they approached and another shot when they knocked on the door. Police left the building after these shots were fired.

Robert L. Rabe, chief of the special operations division of the police force, set up telephone contact with Fuller but was unable to persuade him to answer questions. When the police Chief Maurice Cullinane arrived at the scene about noon he joined in the negotiations but was unable to persuade Fuller to give up.

Fuller was taken to D.C. General Hospital after his arrest. His injuries appeared to be limited to mouth and lip cuts suffered in his struggle with officers who finally subdued him.

Lt. George Bradford, 36, of the police special operations division, suffered a minor wound to the shoulder from a bullet fragment and was released after treatment at Washington Hospital Center. He returned to the scene of the siege before its climax.

An unidentified D.C. fireman suffered undetermined chemical burns to his eyes - apparently from the teargas barrage - and was under treatment at the center last night.

Officer David Schrum, 24, of the third police district, suffered a bite wound on the wrist in the struggle with Fuller.

Cullinane told reporters after the incident that it had been "the toughest" barricade situation he had ever been involved in.

"We never had a coherent conversation," Cullinane said. The police chief added that Fuller said at one point that he was "God" and the police were the "devil".

After hours of trying to negotiate, police spokesman Joseph Gentile told reporters that conversation with Fuller had failed and that the police would try to "extricate" him from the building.

Moments later, policemen stationed in an apartment across the courtyard from where Fuller was barricaded, began firing the first of more than 30 tear gas canisters into Fuller's apartment.

Police sharpshooters armed with rifles took positions outside the building. Other policemen were stationed in the complex's stairwells and in apartments adjacent to that occupied by Fuller.

Residents of the complex, a low-income housing development where about 200 families live, streamed into the street as police forces mounted in number. Later others, including a woman with a baby who was helped out a back window, were escorted out of the line of fire by police.

Police would not confirm that Fuller had made any demands. But a friend of his, Robert Harris, said Fuller apparently staged the siege to "attract the attention" of his girl friend.

Harris, who said he had spent the last three nights with Fuller, said Fuller had talked Tuesday night about staging an incident.

According to records at the D.C. Superior Court, Fuller was arrested May 26 in connection with an incident during which Edwin Lee Proctor was shot and killed. He was charged with homicide, but the charge later was changed to second-degree murder.

Fuller appeared before Judge Fred L. McIntyre May 26 and was released by the judge on personal recognizance. Harris, Fuller's friend, said Fuller had been upset since the shooting incident.

Robert Lee, manager of the Clifton Terrace apartments, said Fuller, who is manager of the D & W Sea Food and Poultry Market at 2508 14th St. NW, had lived in the building since November 1975.