JOHANNESBURG, JAN. 13 -- At least 40 South African blacks were killed at a soccer match today 50 miles southwest of here, as police announced the arrest of 10 suspects in a massacre of 35 mourners at a wake Saturday in a nearby township.

Police reported that 40 soccer fans died and more than 50 others were injured after fighting broke out in a soccer stadium in Orkney over a disputed goal. The toll was expected to rise as some of the injured were in serious condition, according to a police spokesman.

Most of the deaths were caused by a stampede at an exit as the crowd rushed to leave the stadium after fighting began between supporters of the two Soweto-based teams.

The weekend death toll reached at least 77 in the two incidents after police reported today the discovery in Sebokeng township of two women's bodies. They had been "necklaced" -- burned to death by having gasoline-soaked, burning tires shoved over their heads. Press reports said they were mothers of two gang members that residents believed were responsible for the massacre.

The African National Congress today echoed charges by its local Sebokeng supporters that police could have prevented the massacre had they acted on repeated warnings that the gang planned to attack mourners attending the all-night wake of a slain ANC activist.

It contested the government's assertion Saturday that ANC officials at the wake had asked for the removal of policemen in attendance, saying all accounts agreed that the police had not shown up until after the massacre.

Police arrested 10 alleged members of the gang Saturday and confiscated several AK-47 automatic rifles said to have been used in the early morning attack on the 200 to 300 mourners attending the wake.

ANC leader Nelson Mandela led a delegation to Sebokeng today to investigate the killings, and tonight his organization charged that the massacre was "not a pure act of criminals." It said the gangsters involved were in contact with local members of the Zulu-based Inkatha Freedom Party led by Chief Mangosuthu Buthelezi.

"This seems to indicate the use of criminals who feel the heat of the community's anti-crime drive . . . in an attempt to wipe out the ANC," an ANC statement said.

The statement said local Inkatha elements had contacted the gang "with an offer of assistance" to help it "neutralize" an ANC campaign to stamp out crime in Sebokeng. It did not charge, however, that Inkatha members had participated in the massacre directly.

Earlier, regional ANC leader Kgalema Motlanthe blamed the massacre on "a band of gangsters" who had been spreading terror in the township, stealing vehicles and raping women. He said the gangsters kidnapped and strangled to death the ANC activist, Mphikeleli Nangalembe, who had been leading the campaign to end the gang's activities in the township.