For many years this conservative black township only 10 miles east of Pretoria, the capital of white-ruled South Africa, has been a symbol of black docility and of people who knew their place at the bottom of a strictly segregated social order.

But in just two weeks' time, Mamelodi has come to stand for something very different: police brutality and black rage.

Angry parents allege that dozens of their children have been beaten by white soldiers and policemen who, they say, have launched a reign of terror to crush political unrest here. Complaints have become so frequent that the police have taken the unusual step of dispatching a senior officer to collect allegations of misconduct and open an investigation.

"It is like they have declared war on our children," said Louis Khumalo, head of the Mamelodi Parents' Association, who says he has received nearly 100 accounts of beatings in the past two weeks.

The allegations have joined a growing chorus of brutality charges against South African policemen and soldiers in the five weeks since President Pieter W. Botha declared a state of emergency, granting security forces broad arrest powers and sweeping legal immunity in enforcing the declaration.

A group of church leaders who met with Botha a week ago presented to him three affidavits from witnesses in the eastern Cape region, alleging the beating of two women, the rape of a third and the cold-blooded murder of a man by a white policeman who reportedly first told the victim, "Botha has said we can kill you like flies."

A participant in the meeting, the Rev. Stanley Mogoba, a Methodist, said Botha "seemed shocked at the details we brought him. When we said that the police seemed to be taking advantage of their powers, he said the indemnity was not a license for them to act as they wanted."

Later in the week, Police Commissioner General Johann Coetzee issued an appeal for witnesses to come forward with complaints about "any individual furthering the violent unrest situation," promising that such complaints would be "properly investigated and acted upon."

A major tenet of the government's justification for the emergency decree is that the tough measures are necessary to restore the confidence and security of the vast but silent majority of law-abiding township residents. But in communities such as this, many residents contend the police themselves have become an element of lawlessness.

Many see themselves, as an elder at the Mamelodi East Dutch Reformed Church put it, "trapped between the police and our own rough element."

Mamelodi was not even on the list of 36 cities and towns designated under the emergency. But that has not spared it from violence nor from a harsh police reaction that may have fatally damaged the political moderation for which this community of 240,000 was once noted.

One symbol of that moderation, Mamelodi Mayor Alex Kekana, who served 31 years in local governing bodies here, resigned this month after his butcher shop was stoned by youths.

"I thought I had better call it a day," he said in an interview. "After trying to bridge the gap between our people and the government for so long, I really saw no alternative."

Like so much of the unrest that has wracked South Africa the past year, residents here trace their troubles to the apartheid system of racial segregation.

Less than 40 years ago, blacks lived in scattered neighborhoods around Pretoria, as they did around most of South Africa's major cities. But the white Afrikaner nationalists who came to political power in 1948 decreed strict residential segregation. The idea, as it was expressed then, was to eliminate racial "friction" -- by pushing blacks as far from the central city as practical.

Built against a hill, Mamelodi was opened in 1952 and quickly became a magnet for black migrants fleeing rural poverty. By 1968 it had exceeded all official population projections, and the government banned further migration and opened instead men-only hostels for workers, who had to leave their families behind.

Nearly 30,000 men now live along the edge of the township behind barbed wire in squalid, tin-roofed barracks with 10 to a room. Living conditions here are among the worst in South Africa, and the men are cut off from not only from their families but the community their compound borders.

"These people are total strangers in the township," said Nico Smith, a Dutch Reformed clergyman who preaches in Mamelodi. "For them apartheid has created a terribly destructive alienation."

Things began to fall apart three weeks ago when a hostel dweller who had been robbed by three local youths retaliated by killing a 19-year-old high school student.

His burial the following Sunday, Aug. 11, set off violence that pitted the police and hostel dwellers against community residents. Youths attacked the hostels, killing one man whom they doused with gasoline and set ablaze. The hostel dwellers then set upon the township, damaging nearly 200 houses and randomly beating youths.

Witnesses contend the police on the scene stood by passively until the hostel dwellers and the youths faced off outside the cemetery. Photographs taken that day show policemen in an armored vehicle looking on while club-wielding hostel dwellers storm by.

"The police actually encouraged them to go and assault the kids," said Khumalo, a pharmacist and father of two.

Eventually the police intervened. A 12-year-old girl was killed by a bullet while watching the melee from a neighbor's yard.

Since then, policemen and soldiers have maintained a heavy presence in town. At least two other youths have been shot and a dozen more arrested and charged with "public violence."

Residents have retaliated with a two-week boycott of white businesses in Pretoria and by supporting a student boycott of the township's 10 public schools.

Khumalo's parents organization has hired a lawyer to compile affidavits from victims of alleged brutality. He also said he had talked to three girls who contend they were raped by soldiers.

"They're so terrified they won't lay charges," said Khumalo, who added that parents won't let their children return to school until the police and soldiers withdraw.

A police spokesman in Pretoria characterized Khumalo's allegations as "very serious" and said victims of alleged misconduct should file charges with the police. But Lucas Mabusela, a Dutch Reformed clergyman, said, "People feel it is useless to go to them."

Former mayor Kekana, a short chunky man with a politician's smile and a broad sense of humor, said, "Since 1976 we've been hanging on threads, begging the government for changes and nothing has been done. Life is just empty for us under the present government."

Kekana said Mamelodi's reputation for tranquillity now seems like a myth: "It was never as quiet as people thought. Whatever black people are suffering, we are suffering the same."