Twenty four people were killed and 60 wounded yesterdays when a bomb exploded in Angola's second largest city, Huambo, the official Angolan news agency Angop reported.

In a telexed report to Reuter, the report quoted the Angolan Information and Security Directorate as saying that several people belonging to a 300 member group trained in South Africa had infiltrated into the country and had been arrested.

The government communique charged that the bombing in the central Huambo market yesterday morning was part of preparations by South Africa for an attack on Angola, Angop said.

The statement added that the background to the attacks was the speech by Defense Minister Iko Carreira on Monday in which he said South Africa was preparing to attack Angola.

[A U.S. State Department spokesman said there continue to be sporadic reports of guerrilla activity by the National Union for the Total Independence of Angola (UNITA), one of the losers in the civil war, in southern Angola. It is possible, the spokesman said that the bombings, which have been conducted by the guerrillas in the past, were still being carried out.]

It was the second bombibg in the area in the last few days, the agency added. A bomb in the market at Canhe and killed 16 people and wounded 54, it said. It gave no date.