Soviet authorities said yesterday that U.S. agents had done more than $200,000 damage to the Aeroflot plane they searched Tuesday at Dulles Airport and accused the Americans of endangering the aircraft's safety by tampering with its instruments, Washington Post correspondent Kevin Klose reported from Moscow.

In Washington, State Department spokesman Dean Fischer announced that the U.S. Embassy in Moscow had delivered a note formally rejecting an official protest of the incident, in which Customs agents, acting on an inaccurate tip, seized three boxes of electronic gear they said they thought the Soviets might be trying to sneak out of the country. Fischer called the Soviet protest note "highly inflammatory" and "part of an unseemly propaganda campaign."

"They evidently hope, through distortion and exaggeration, to convert this customs examination into an international incident," he said.

At a Moscow press conference, the Soviet crew accused agents of endangering their Ilyushin jetliner by opening instrument panels and equipment access hatches throughout the plane, by tampering with navigation equipment that is kept in a baggage compartment and by slashing open cartons.

The chief U.S. Customs official announced Thursday that none of the seized items was defense related. He said the boarding of the Aeroflot plane was not designed to harass the Soviets, and said he saw no need for an apology.