An unemployed exterminator who had barricated himself inside his Connecticut Avenue apartment to forestall an impending eviction was found after heavily armed police stormed the apartment.

Police said Edward J. Callen, 54, of the parkway Apartments at 3220 Connecticut Ave. NW was found lying in bed with a gunshot wound in the head after police burst into the second floor apartment about 2.30 p.m. Police said his death apparently was a suicide.

For two hours preceding discovery of the body, a busy stretch of Connecticut Avenue had resembled an urban war zone, with police sharpshooters stationed on the surrounding rooftops, traffic closed off for blocks in both directions , police vehicles clogging every available alley and highway, and flak-jacketed special operations division officers stationed behind parked cars.

The alert was first sounded when two U.S. marshals, armed with a Superior Court eviction order, knocked a hole through Callen's door with a sledgehammer and heard a loud "pop" from inside. Thinking the sound was that of a gunshot, the marshals immediately summoned the police.

D.C. homicide investigators later attributed the "pop" to an aerosol can that burst inside the apartment, apparently because of the extreme heat.

Investigators said it was impossible to tell immediately how long Callen had been dead, but that it appeared he had shot himself some time before the marshals arrived at his apartment. An autopsy is scheduled for today.

Callen's sister was summoned from Rockville during the height of yesterday's activity, in the hope that she might able to communicate with her brother, but it was unclear last night whether any such attempt was made.

A building maintenance man told police that Callen had experimented with different kinds of burglar alarms for his apartments, and he owned two handguns. After the discovery of Callen's body, police recovered the two guns described as a .45 caliber pistol and a caliber weapon.

Customers at the shopping centre on the northeast corner of Connecticut Avenue and Macomb Street found their cars trapped there throughout the incident, while they themselves were ordered, along with other civilians, to stay several hundred yards from the scene.

According to police, Callen had quit his job with Paramount Pest Co. last May and the rent check for that month he sent to Daro Realty Co., which manages the building was returned for lack of funds. Afer Callen made no further attempt to pay his rent. Daro sought and obtained an eviction order according to a company spokesman.

Callen lived alone in his apartment and other residents spoke of him yesterday as a quiet, but personable neighbor.

"I never saw Mr. Callen much, but the few times I spoke to him he was very nice and talkative," said Elsa Sandusky, who lives in an adjacent apartment. "There was never any noise coming from his apartment. He never had any visitors that I know of."

Another neighbor said the Parkway Apartments were usually so quiet "you could hear a pin drop at night."

"That's why all the confusion today was so terrifying," she said. "It's not the kind of building where you could expect something like this to happen."