VENTERSDORP (Sapa-AP) - The mother of a 15-year-old murder suspect said Monday that her son struck a notorious white supremacist leader with an iron rod after the farmer refused to pay him, a slaying that heightens racial tensions as South Africa prepares to host the World Cup.

"My son admitted that they did the killing," the mother said in an exclusive interview with AP Television News conducted in the Tswana language from her two-room cement home in Tshing township on the outskirts of Ventersdorp town.

She said she spoke to the teenager at Ventersdorp police station on Saturday after he turned himself in along with his alleged accomplice, a 28-year-old farm worker, following the slaying of Eugene Terreblanche.

Police have refused to identify either of the suspects by name.

Under South African law, a minor accused of any charge cannot be identified without permission from a judge.

Terreblanche, 69, was leader of the far-right Afrikaner Weerstandsbeweging movement, which said it planned to march Monday on the police station to demand the police bring out the two suspects. Police say the two have been charged with murder and will appear in court Tuesday.

Officials appear anxious to show they are swiftly handling the crime, which comes just 10 weeks before South Africa becomes the first African nation to host the World Cup soccer tournament.

Terreblanche's slaying also comes at a time of heightened racial tension in this country once ruled by a racist white regime that only gave way to democratic rule in 1994 after years of state-sponsored violence and urban guerrilla warfare waged by the now-governing African National Congress.

The mother said her 15-year-old son told her that when he and his co-worker asked Terreblanche for their money, he told them first to bring in the cows. After they had brought in the cows they again asked for their money, which he then refused to give them.

"He said that the (laborer) man told him to wait while he went to the storeroom. He came back with an iron rod. He started hitting Terreblanche, with four blows to the head. Then my son says he took the iron rod and hit him with three blows," the mother said.

"My son was a person who doesn't like to be in trouble," she said softly, appearing a bit bewildered and scared.

At the farm Monday, a big grader was being used to dig a hole for Terreblanche in the family graveyard, where he is to be buried after a church service in Ventersdorp on Friday.

"This was such an unnecessary thing," Terreblanche's brother, Andries, told the AP, as he sat on a gray marble grave. "We are not racists, we just believe in purity of race."

AWB's members still seek to create an all-white republic within mostly black South Africa.

The group's leaders have been using Terreblanche's killing as a rallying point for their cause, with Secretary-General Andre Visagie claiming Sunday that Terreblanche's brutal death was "a declaration of war" by blacks against whites.

He also warned countries against sending their soccer teams without protection to "a land of murder."

Visagie and other members of the group have blamed African National Congress Youth Leader Julius Malema, saying he spread hate speech that led to Terreblanche's killing.

Malema incited controversy last month when he led college students in a song that includes the lyrics "kill the Boer." Boer means farmer in Afrikaans, the language of descendants of early Dutch settlers, but also is used as a derogatory term for whites.

The song sparked a legal battle in which the ruling ANC party challenged a high court that ruled the lyrics as unconstitutional.

The ANC insists the song is a valuable part of its cultural heritage and that the lyrics - which also refer to the farmers as thieves and rapists - are not intended literally and are therefore not hate speech.

Visagie said the 15-year-old suspect was a casual worker and that the 28-year-old man was a full-time employee who had been taking care of the garden of the family home in Ventersdorp.

Terreblanche had been spending most of his time there since he had heart surgery a few weeks ago.

Terreblanche had previously been convicted for a brutal attack on two black farm workers and was sentenced to six years in prison.

He re-emerged in 2004 as a born-again Christian with renewed vigour for his cause. The movement always has been on the fringes, estimated to have no more than 70,000 member at its height in the early 1990s out of a population of nearly 50 million.

Police said Terreblanche was lying on his bed when he was attacked between 5 and 6 p.m. on Saturday.

The mother's account that there was only one murder weapon - an iron rod - did not fit police reports that a machete and a wooden staff with a rounded head were the murder instruments found at the scene.

Visagie said Terreblanche was bludgeoned so badly he was barely recognizable and described a gory murder scene indicative of great rage when he visited the farm on Sunday.

"There was blood all over the place, pools on the mattress, the pillow, the floor and splatters on the walls and ceiling," he said.

"The deductions I make is that he was killed almost instantaneously but the murderers kept on beating his body and chopping his corpse with the panga (machete)."

Terreblanche, who would appear at rallies astride a black horse, founded the movement that was to the right of South Africa's apartheid government in the 1970s. Masked AWB "storm troopers" in black or khaki uniforms terrorized blacks in the years leading up to majority rule. The AWB's red, white and black insignia resembles a Nazi swastika, but with three prongs instead of four.

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