S. Africa Blasts Kill 12 on Election Eve : Violence: A 220-pound bomb rips a taxi stand in nation’s deadliest wave of right-wing terrorism. Troops are mobilized to ensure safety at polling places.

A 220-pound bomb ripped through a crowded taxi stand used by blacks in this conservative city Monday, killing 10. Two more people died later in a restaurant blast in Pretoria as the deadliest wave of right-wing terrorism in the nation’s history hit South Africa on the eve of all-race elections.

The attacks, the most recent of more than a dozen that have killed 21 and injured almost 200 in the past two days, appeared to be part of a campaign by white extremists to discourage South Africans from voting in the three-day elections that will bring blacks into government for the first time.

Political leaders, seeking to reassure worried South Africans, announced Monday the biggest peacetime military call-up in the country’s history to ensure that the 9,000 polling stations will be safe.

Besides army troops, 100,000 police officers, twice the number that was originally planned, will be on guard at polling booths beginning today.

“A group of desperate people, small handfuls of radicals, have declared war on the rest of this society,” President Frederik W. de Klerk said. “We will not rest until they have been tracked down, convicted and punished, as they deserve.

“Our contingency plans for the elections are in place,” he said. “While incidents such as these obviously constitute a risk, I want to assure the public that we will do our best to assure they can vote safely.”

It was difficult to tell how many of the expected 20 million voters might be deterred from casting ballots by the resurgence of terrorist attacks, especially if more innocent people are killed in the next few days.

But many South Africans said the attacks, part of the biggest bombing campaign since the then-banned African National Congress was waging guerrilla war on the white-minority government in the 1980s, have made them more determined to make the elections a success.

Johann Kriegler, head of the Independent Electoral Commission, promised Monday that the elections will go ahead, “bombs or no bombs.” The voting begins today with elderly and disabled South Africans casting ballots at 500 special polling stations. The entire country goes to the polls Wednesday and Thursday.

Although Kriegler said Monday’s killings were tragic, he added, “We have come light years in four years, and we will not be deterred by minor incidents.”

A white suspect was arrested and questioned Monday in the bombings in Germiston and in Johannesburg a day earlier, police said. They declined to specify the suspect’s political affiliation, but Gen. Johan van der Merwe, commissioner of police, promised that “a breakthrough is imminent.”

Police offered a $300,000 reward, the largest in this country’s history, for information leading to the arrest and conviction of the Germiston bomber. Authorities said the Johannesburg car bomb, which killed nine and injured more than 100, and the larger Germiston bomb were probably prepared by the same person, someone with considerable experience with explosives.

Right-wing leaders insisted Monday that their organizations were not responsible for the bombings. But a caller to an Afrikaans-language newspaper late Monday claimed that his right-wing group was responsible for the Germiston blast and warned that it “would be a picnic compared with what is to come.”

Political analysts said all the attacks carried the signature of militant rightists, who have vowed to boycott the elections and demand an autonomous homeland for the Afrikaner descendants of the first white settlers. “What is clear is that there is a new element in right-wing terrorism,” said Wim Booyse, a political consultant in Pretoria and an expert on the white right. “And these blasts have risen to a level that the country has never seen before.”

Booyse said the attacks were probably part of a last-ditch campaign by one or more of the shadowy, highly trained groups on the right, which have been silent for weeks.

Since Sunday, a dozen bombs have exploded at polling stations, government offices and other sites, although there have been no serious injuries in those incidents.

ANC President Nelson Mandela visited victims of the Johannesburg blast Monday. Speaking to reporters later, he said he is convinced that the nation’s police commanders want to end the violence. “I hope the government acts in a way to remove the impression that it is a government of weakness, unable to rise to the challenge that is posed by madmen who are killing innocent people,” he added.

In Pretoria, the explosive device was tossed into a crowded restaurant catering mostly to blacks shortly after 8 p.m. Monday, killing two and seriously injuring at least six, police said. Witnesses said the bomb was thrown from a passing car carrying two young white men.

The bomb in Germiston, a white industrial city about 10 miles southeast of Johannesburg, was planted in a trailer parked amid taxi vans near downtown. It exploded at 8:45 a.m., shattering windows in a four-block-square area, tossing parts of cars and bodies onto roofs of nearby buildings and destroying 10 minibus taxis. A grocery store building also was destroyed.

“This bomb was to scare away the voters,” said Izzy Naigi, a spokesman for the Congress of South African Trade Unions, an ANC-aligned labor association with local offices near the scene. “We were expecting something like this, and we expect more to come.”

The explosion occurred on a city street where black taxi drivers collect passengers and fix their vehicles; the dead included drivers, passengers and clerks in the store. Whites in the area had complained in recent months that the illegal taxi stand had increased the crime rate in the area.

The blast heavily damaged the adjacent, two-story Good Hope Center, an apartment building run by a charity for poor and elderly whites. Many of the 80 people there were injured.

“I’d never heard anything that loud in my life,” said Piet Bothes, 50, who runs the center. “It’s hard to believe that human beings can do things like this. All I can say is they weren’t Christians, because Christians couldn’t do anything like that.”

Meanwhile, in Cape Town, the white-dominated Parliament met for the last time Monday to amend the constitution to recognize the Zulu monarchy and allow Mangosuthu Gatsha Buthelezi’s Inkatha Freedom Party to participate in the voting. Buthelezi called off his election boycott last week. His decision has eased tensions in Natal province, where supporters of Buthelezi and Mandela have been battling for a decade, leaving thousands dead.