After nearly two years of official silence about one of the most extraordinary and unexpected events in modern Chinese history, Peking has begun to talk about the Tienanmen square riot of April 1976.

A somewhat vague account of the historic demonstration in the official People's Daily and a more forthright eyewitness report in a Hong Kong magazine with Communist backing Mark China's first attempt to discuss publicly an event that is still political dynamite.

The men now in power in Peking want to show sympthy for the rioters, whose suffering after the demonstration still inflames passions in China. But they seem to be wondering if they can safely do so. Tienanmen was, after all, of the few spontaneous political events ever to occur in the nation's tightly organized capital city.

Some men still in power made what were, in hindsight, serious mistakes in dealing with the riot. So the new public recounting of the events of April 5, 1976, also represents one more jab in an undercover sparring match between political factions in Peking.

About 100,000 people, by official count, filled the main square of Tienanmen in central Peking that day to join or watch an unprecedented public protest against official neglect of the memory of Premier Chou En-lai.

Chou, a popular and pragmatic leader, was the hero of veteran party officials like Vice Chairman Teng Hsiao-ping who now make policy in China. But Chou was reviled by the dogmatic Maoists who controlled the Chinese media at the time.

The new accounts say these dogmatists managed to spark the riots by trucking away early in the morning of April 5 the wreaths that had been placed in the square honoring Chou.

By day's end, more than 100 people had been injured, several vehicles burned, at least one building looted and burned and perhaps thousands of people arrested. But the official accounts at the time did not explain what exactly had started the riots or what happened to those arrested.

The latest issue of the new Hong Kong journal Cheng Ming, apparently published with Peking backing, says that "on the morning of that day, people began to gather at the square. A van equipped with the public address system urged the crowds to disperse. People flocked to the van and questioned the right to take away the wreaths. Protests and arguments soon developed into heated exchanges. Someone shouted: "Overturn the vehicle."

An official who confronted the crowd accused "Premier Chou of being 'the arch capitalist roader in the party.' This enraged the mourners. When he tried to get away and ran toward the Great Hall of the People, many people chased after him. After ascending the steps of the Great Hall, army guards let him enter the building but stopped his pursuers."

In a sign of the lingering resentment toward Shanghai, where the dogmatists had their base of support and where people speak with what is to Peking ears a heavy accent, the Cheng Ming writer said another official emerged and yelled in a "heavy accent," "Who among you dares to seek entry? What place is this? Get out of here, all of you."

"Judicial police," including "hooligans, teddy boys and the like from Shanghai" soon appeared to try to quell the disturbance, the account said.

It repeated a broadcast, calling for order, made that day by Peking Mayor Wu Teh. Wu is one of those officials thought to be under fire for his Tienanmen role. He is not named in the Cheng Ming account, but he is quoted as calling Teng Hsiao-ping, since restored to great power, "an unrepentant capitalist roader." Foreigners who were at the square on that day say Wu did not actually mention Teng by name and the vice premier was only identified in versions of the speech printed in the press two days later, when Teng was vaguely blamed for the riot and officially removed from all his posts.

The account praised two current leaders, Yeh Chien-ying and Li Hsien-nien, for declining to pursue the investigation of the riot, but indirectly criticized the current Peking army commander, Chen Hsi-lien, for participating in that investigation.

People's Daily revealed the fate of some of the rioters in a long account of efforts to honor Chou by students at Peking's Tsinghua University. The articile does not mention the Tienanmen incident by name but it is clear from the context that it is the event which led to the punishment of a group of university students who prepared a white paper flower in memory of Chou.

"One of them was arrested and later released, three were jailed and the rest were criticized and struggled against. It was incredible that those of the younger generation who were brought up to live under the red flag were suffering under a fascist dictatorship," the newspaper said.

Both articles said all those unjustly imprisioned for their part in the riots were released six months later, when Teng's admirers overthrew the dogmatists and began to restore his and Chou's good name. There have been no such demonstrations since. But now that it has happened once, in the constantly shifting political winds of China, many Chinese think it could happen again.