Police using tear gas and firing warning shots today dispersed thousands of African students marching through the streets of Soweto, Johannesburg's black township, to protest the government deecreed steep increases in housing rents - ranging from 30 to 80 per cent - that take effect May 1.

Three African youths were admitted to the Soweto hospital with gunshot wounds, which doctors described as flesh injuries. A police officer was injured when students began throwing stones at police vans.

Today's rioting is the most serious racial confrontation in South Africa this year, and the first since early February, when some 6,000 students protested final examinations by marching and burning their textbooks.

Last year, more than 500 Africans were killed during six months of sputtering anti-government riots in several South African cities over issues covering language and curriculum in black militant leaders, alleged police persecution, the lack of African political power, and unequal living conditions for South Africa's 18 million blacks, who out number whites by more than 4 to 1.

The demonstrations today were triggered by a new grievance - the government's unexpected announcement last week that African housing rents would almost double.

The move will affect virtually all residents of the sprawling township of more than a million since South Africa's new home ownership plan for blacks has not yet gone into effect. All Soeweto homes, which number over 100,000 are owned by the government.

Students marched today on the Urban Bantu Council chambers, a black administrative bodya that serves the 26 sub-townships that make up Soweto. It was scheduled to hold its monthly meeting tonight.

At morris Isaacson high school in Orlando, police estimated that 2,000 students gathered early this morning. Many carried angry banners declaring: "We will not pay," and "Away with capitalism."

Leaders of the Soweto Student Representatives Council said they planned a peaceful march on Soweto's white administrative offices to protest the rent increases. When police riot vans appeared, leaders decided to abandon the march and instead asked students to go home and urge their parents not to pay next month's rent.

The presence of police at the stadium where a crowd had formed also caused it to disperse.

At the Bantu Council chambers, youths throwing stones and bottles broke most of the windows, officials said this afternoon. Police dispersed the crowd with tear gas shortly after noon.

Students leaders said the council was a target because it "has finally demonstrated that it is acting against the interests of black people. The UBC has consistently been used by the authorities to oppress our own people."

The student representatives group called on the Bantu Council members to resign and threatened, "We urge members of the UBC not to underestimate the anger of our people and the last thing we want to see is confrontation between black and black."

Police reported several isolated incidents: a garbage collection truck was set on fire; a bread van and a soft drink truck were looted, and a beer hall looted and then set ablaze.

Police officials said they made a concerted effort today to avoid using weapons or aggraving the tension. Brig. Gen. Jan Visser, Soweto police chief, told reporters: "We are here to keep peace. We are not murderers. It is only if they start burning buildings or molesting people that we will act."

Student spokesmen would give no indication of their plans for future demonstrations over the rent issue. But few here believe the protests are over.

There is also growing talk about plans for demonstrations on June 16, the anniversary of the first eruption of racial violence in Soweto last year.