A marcher fired shots in Red Square not far from Soviet leaders during Wednesday's Revolution Day parade, and thousands of angry citizens held the first protests ever sanctioned in Moscow on the major Soviet holiday.

The shooting was the most violent incident in a tumultuous day as clashes were reported in some areas between authorities and anti-Communist protesters, and thousands of Communists openly criticized President Mikhail S. Gorbachev.The Soviets also displayed one of their deadliest missiles and other military equipment.

During the traditional parade, a man fired two shots into the air about 80 yards from the Lenin Mausoleum, where Gorbachev and other leaders were watching, reports said.

No one appeared to have been hit and police quickly grabbed the unidentified man, said Tass correspondent Sergei Vozianov, a correspondent of the official news agency's video branch who witnessed the incident. Vozianov said it was not clear if he was aiming at anyone.

The Tass news wire quoted KGB officials as saying the man fired into the air with a sawed-off shotgun. It said the gunman was from Leningrad but gave no further details.

In the Baltic republics, paratroopers reportedly stormed a conservatory building and beat students who were planning anti-Communist demonstrations, according to the independent Baltic News Service.