A South African official who blew the whistle on alleged corruption in the building of a stadium for the 2010 World Cup has been shot dead by unknown gunmen.

Jimmy Mohlala, a member of the local organising committee for the World Cup, was murdered late on Sunday at his home in the northeastern city of Nelspruit.

"He was shot by two unknown men who were wearing balaclaves...the gunmen had been lying in wait outside the Mohlala home in an unmarked vehicle," a statement from the Mbombela Local Council Municipality said.

His son, who was with him, was also shot and wounded by the assailants who later fled the scene

Mohlala was a former vice president of the South African Football Association and headed the local council of Mbombela, where the stadium is being built in Nelspruit for the World Cup.

Danny Jordaan, the head of South Africa's organising committee, said his death was a "huge setback" for organising the event in Nelspruit.

Mohlala made headlines a year ago after it was reported that some members of the ruling African National Congress (ANC) wanted him sacked for allegedly turning in a colleague over graft claims in the construction of the Mbombela stadium.

His claims sparked an investigation into a range of allegations, including the manipulation of tenders in 2010 construction contracts.

The 46,000-capacity Mbombela stadium, scheduled for completion this year, is one of 10 venues for the 2010 World Cup.