Behind the official curtain of silence imposed under South Africa's nationwide state of emergency, a pattern of intensified violence and retribution slowly has begun to take shape.

Hundreds of activists are rounded up around the country, and terrorist bombs go off at restaurants in downtown Durban and Johannesburg and at a shopping center. A 9-year-old child is killed by a soldier's stray bullet in Soweto, and a black policeman is blown apart by a hand grenade.

At least a dozen blacks fall victim to the "necklace," the grisly ritual of execution in which burning tires are placed around the necks of those branded as collaborators with white minority rule. A high-ranking black police official who ordered his men to open fire on demonstrators three months ago is himself gunned down by assassins.

The government contends that the emergency, imposed June 12, has succeeded in reducing the level of civil unrest and intimidation that it says must be curbed before South Africans, white and black, can get on with the process of reshaping their political future.

Pretoria's intention, information spokesman Casper Venter said Friday, "is not only to prevent murders and killings and rioting, but . . . to restore law and order, calm and tranquility, in order to create the climate in which the government can continue with its reform process, can continue with its negotiations with black leaders."

But the average toll of nearly five unrest-related deaths per day remains what it was before the new crackdown began, and the atmosphere in many black townships remains, in the words of Anglican Bishop Desmond Tutu, "sullen and fearful."

Rather than creating a prelude to negotiations, critics such as Tutu contend, the emergency has further shrunk the limited middle ground between Pretoria and its most militant opponents, and set off a tit-for-tat war of retribution in which "soft targets" have become acceptable victims in the eyes of the operatives of the outlawed African National Congress.

All of which could move South Africa another step down the road to civil war.

The government's show of force clearly has succeeded on some levels. It has shattered the illusion -- held by some in the West, although by few of the government's opponents here -- that Pretoria was near collapse, and that an intensification of civil unrest, coupled with increased western diplomatic and economic pressure, would somehow cause the early downfall of the apartheid system.

It has also done serious damage to liberal political organizations that traditionally have chosen to function in an open, above-ground style.

"It's been a great setback for groups like us," said Sheena Duncan of the Black Sash, a long-established civil rights group here. "While we can still help blacks needing advice, we've had to suspend at least half our work, just about everything that deals with political issues."

But for those further to the left who are willing to operate clandestinely, the emergency appears to have had less impact. The street networks of the United Democratic Front, the largest antiapartheid coalition, remain largely intact. Meetings are held regularly. Many leaders remain active, although underground, biding their time until the new crackdown eases.

"Our principle is that when the enemy is kicking, keep calm," explained one UDF activist last week. "Wait until he stops, then we can start kicking again."

The UDF has been the main target of the crackdown, as it was during last year's emergency. Detentions are taking place over a much wider area than last year and at double the pace, according to a spokesman for the Detainees' Parents Support Committee, which estimates that at least 4,000 people have already been pulled in.

"They want to smash us, and they have fallen back on what is for them a very sure-fire method," said the Rev. Allan Boesak, the Dutch Reformed minister who is a founding patron of the front. "The thing is, it is not working," he said, noting that the UDF added 34 new community organizations to its coalition during 1985 despite the intensifying crackdown. "In a year of the worst repression, with all the major leadership in jail and no public meetings, we actually increased our membership."

One of the major changes in recent weeks has been the shift in the nature of unrest deaths. Until recently, at least 60 percent of those deaths -- estimated at more than 1,800 since the disturbances began in 1984 -- were caused by members of the security forces shooting blacks, according to the South African Institute of Race Relations.

But since the new emergency began, according to the government -- whose figures cannot be independently verified because of emergency restrictions -- about 70 percent have been the result of black-on-black violence.

The government sees this statistical shift as vindication of its claim that black radicals are holding hostage the vast majority of moderates by use of violence. But the "necklaces" and other acts of vengeance are also a setback for the government's stated policy of drawing the moderates out of their foxholes.

UDF sources say they do not condone the murders, but believe such acts of revolutionary retribution have damaged the government's extensive network of informers by raising the stakes for those considering collaboration with the state. The lack of accurate, current information is also one reason, some believe, why many prominent UDF and trade union leaders were passed over during the initial roundup two weeks ago.

When they first imposed the emergency, South Africa's leaders indicated it was a temporary move designed to fill the gap until a set of stringent new security measures took effect. Those laws are now in place, but officials have made clear that they intend to continue the emergency until "stability" is restored to the townships. They do not want to repeat the mistake they made in March of ending last year's partial emergency while the unrest continued to rage.

The price for maintaining the sweeping restrictions could be high. A new set of largely symbolic U.S. economic sanctions now seems inevitable, as does a shift in British Prime Minister Margaret Thatcher's adamant stand against sanctions. Such measures would undoubtedly aid opposition morale here.

"This is a civil war where one side has all the guns, so we are forced to look to the international community for help," said Boesak.

Then there is the international perception that, with its new detentions and sweeping restrictions on press freedom, South Africa has slipped, in the words of Business Day, a newspaper here, "from authoritarianism to totalitarianism." That view is also damaging for a state that has sought to portray itself as a beleaguered member of the western world with a claim to western sympathy and cooperation.

In the end, government officials here cling to several ideas: that the black moderates will come forward once enough radicals are locked away; that the government has considerably more firepower than it has yet employed, and that the use of more state power will inevitably produce the desired result.

"The government believes that it can contain the situation indefinitely by use of force," wrote the Commonwealth Eminent Persons Group in a recent report. The group said it was "left with the impression of a divided government. Yet even the more enlightened ministers whom we met seem to be out of touch with the mood in the black townships, the rising tide of anger and impatience within them and the extent of black mobilization."

Every once in a while, however, the realization seems to slip through to even the most hard-line of the government's security officials that perhaps their strategy has gone awry and that they may be arresting the very persons with whom they need to negotiate.

Law and Order Minister Louis le Grange conceded in Parliament two weeks ago, "There are presently people in detention who may be urgently needed for dialogue." But, he quickly added, "because of their activities, it is not possible to talk until law and order is maintained." GRAPHIS/One: Lucas Mangope, president of the black "homeland" of Bophuthatswana, attends the funeral of Brig. Andrew Molope, the police chief gunned down last week. Three months ago Molope had ordered an assault on black protestors at a rally.