A young Soviet citizen who wanted to emigrate to the United States killed himself tonight by exploding a homemade bomb strapped to his body when Soviet security officials stormed the U.S. Embassy here in an effort to remove him.

U.S. Ambssador Malcolm Toon, who approved the Soviet commando-style raid, said the man was badly burned but apparently still alive when he was taken away in an ambulance.

A spokesman for Skifosovski Emergency Clinic said the man was dead on arrival.

The Man, described only as a 27 year-old merchant seaman, entered the embassy eight hours earlier saying that he was a political dissident and that he "hated Brezhnev," referring to Soviet President Leonid Brezhnev.

After a discussion with U.S. officials that he apparently regarded as unsatisfactory, the man shouted that he had a bomb strapped to his body and would set it off unless given assurances that he would be allowed to emigrate.

Two hours later, after all personnel and dependents were evacuated from the north wing of the embassy, which houses the consular, press and cultural sections as well as several apartments for U.S. diplomats, Toon called for Soviet assistance.

Tonight, the ambassador said the unprecedented U.S. permission to Soviet authorities to carry out such a raid inside the U.S. Embassy did not involve any breach of security.

"Since it was apparent that the man was unbalanced, and since he appeared in our view to represent a threat to the safety of American personnel and property, and since he was a Soviet citizen, we called upon the Soviet authorities for help," Toon said.

He added that the Soviets were told they could handle the situation "as they saw filt." For the next six hours Soviet officials negotiated with the man in an effort to persuade him to leave the embassy peacefully.

"At this point we don't know what happened," Toon said after the man was evacuated. "The Soviets either used force or threatened to use force and the young man pulled the pin and in effect blew himself up."

The homemade device was a small gray metal box containing black powder.

Earlier in the evening, journalists confined to the rear of the U.S. compound heard several explosions from the direction of the consular officies that sounded like bursting tear gas canister. Soon after, Embassy consular officer Robert Pringle was briefly overcome by tear gas and was treated by the embassy doctor's office. No other injuries were reported.

Shortly before 11 p.m., the journalists heardd a loud explosion and two smaller ones, presumably the man's homemade bomb and more gas canisters.

Sidewalks in front of the embassy were filled with Soviet plainclothes and uniformed police. Four fire trucks were parked near the entrance.

Tonight's incident was unprecendented, although the embassy has been plagued in the past three years by bomb threats and by desperate Soveit citizens seeking to emigrate. Seven pentacostalists from Siberia complaining about religious pesecution and seeking to go to the United States have been living in the embassy compound since last June.

Other recent incidents include a devastating fire in 1977, claims of Soviet electronic eavesdropping and Soviet microwave bombardment of the building.