Many people have been killed in an "all-around civil war" in China's most populous and perhaps most faction-ridden province, an official Chinese radio broadcast had disclosed.

The broadcast from the huge southwest province of Szenchwan, monitored here Wednesday, indicated that the fighting ended with the October purge of four leading Peking radicals; but it called on Szechwanese to "eliminate the remnant poison" of those who caused the trouble.

It was the first clear sign of the severity of recent political strige in Szechwan and seemed to indicate that the province never really settled down after its well-publicized bloody confrontations during the cultural revolution 10 years ago.

"Because of sabotage by the gang of four," said the broadeast, referring to disgraced radical leaders Wang Hungwen, Chang Chun-Chiao, Yao Wenyuan and Mao Tse-tung's widow, Chiang Ching, "in our Szechwan, civil war and factionalism did not cease. Many class brothers who had fought shoulder-to-shoulder becames enemies and the precious lives of many class brothers were sacrificed in all-around civil-war."

Combined with reports of serious bloodshed earlier in the northern city of Paoting and the central city of Wuhan the Szechwan broadcast illustrates the enormous problem new Chinese leader Hua Kuo-feng has in sorting out blame and soothing bitterness caused by the killings.Several times during the Cultural Revolution, Peking leaders seemed to have brought Szechwan under control by dispatching troops and by other devices. But violence would flare again as people tried to settle old scores.

Located in a rich valley surrounded by mountains, Szechwan throughout Chinese history had nurtured a reputation as a rebellious "independent kingdom" and was one of the last provices to re-establish its government after the Culturral Revolution purges. The new broadcast from Chengtu, the provincial capital, blames the "gang of four" for incitng the factional activity, although it has been pursued by all sides in the Szechwan political battle.

The province has 80 million people, more than all but seven countries in the world.

"The gang of four built mountain-strongholds, organized factions, used counter-revolutionary double-dealing tricks to sow discord and create incidents, instigated bourgeois factionalism, stirred the masses to struggle against each other and sabotaged revolutionary unity," the broadcast said.

The broadcast was a report of speeches given at a Dec. 24 rally Chengtu attendend by 10,000 representatives of workers, peasants, women and youth in the province. It gave no hint that military units had been sent in to control the factional fighting as occured last month in Fukien Province. Szechwan's bad luck with army involvement in the past may have made Peking think better of it.

The broadcast also provided no details of the fighting, unlike during the Cultural Revolution when Peking wall-posters gave lurid accounts of Szechwan atrocities. In just one month in 1967, reports said that workers killed 70 people in a Chengtu factory, that 100 others were buried alive in a suburb and that 34 headless bodies were found floating in a river. Besides firearms lent by or stolen from army units, wall posters in the late 1960s claimed, the opposing factions used lime, sulphuric acid, DDT and poison gas against their enemies.

"Have artillery pieces been fired in Chungking?" The city's military commanders was asked when summoned to Peking in 1968. "Only double-barreled anti-aircraft guns," he replied.

As a sign of the connections between the Cultural Revolutions days and the present. Szechwan radio reported on Dec. 23 that there had been serious disturbances this year in Ipin Prefecture, important base for the radicals 10 years ago. A married couple who were Ipin party officials, Liu Chieh-ting and Chang Hsi-ting, had led the fight then against provincial leader Li Ching-Chuan and for a time had served in the provincial leadership themselves. But they disappeared from sight and Li, after being purged in 1967, was rehabilitated in 1973 and given a high post in Peking. The Ipin radicals, according to the broadcast, reacted violently.

During memorial activities for Mao in September, "they created incidents in a planned and organized way, stormed funeral halls, beat up and injured militiamen on duty, causing serious consequences. In Ipin, they ran wild and did all kinds of evil and people were extremely angry," the Dec. 23 broadcast said.

Without going into the details of Szechwan's trouble, Peking leaders have admitted that it and a handful of other provinces were hurt economically by this year's political strife. In Szechwan's case, this is particularly serious, because in the past it has been able to export much grain and other food for less fertile parts of the country.

Wang Hung-wen and Chang Chun-chiao are blamed in the broadcasts for encouraging their allies in Szechwan to try to eliminate their opponents. The Ipin braodcast said that people "saw clearly and hated in their hearts the gang of four, these ferocious enemies. They have waited long for the day for settling accounts for their crimes."

Despite appeals from Peking for restraint in hunting down radical followers in the provinces, the most recent broadcasts from Szechwan - like those from other highly volatile provinces - do not repeat the ritual formula for lenience toward mistaken and misguided individuals.