S. Africa admits troops still in Angola despite withdrawal pledge. Angola says S. Africa units hit oil complex

The chief of the South African Defense Force, Gen. Constand Viljoen, admitted yesterday that South African troops were still in Angola -- more than a month after Pretoria claimed they had withdrawn. General Viljoen's admission came after an Angolan statement that its armed forces had intercepted a South African commando unit as it was preparing to sabotage a refinery in the oil-rich enclave of Cabinda.

Pretoria's admission will no doubt strengthen accusations that the South African government is closely involved in the Angolan civil war and is actively supporting the anti-government National Union for the Total Independence of Angola movement (UNITA).

Two South African soldiers were killed and a third captured in a clash near the Malongo oil complex, an Angolan communiqu'e said. The South African unit was equipped with shortwave radios, walkie-talkies, silencer-equipped guns, contact mines, and fire bombs, according to Angola. The oil complex is operated by the United States company, Gulf Oil Corp.

Before Viljoen acknowledged that ``small elements'' of the South African Defense Force (SADF) were involved in intelligence gathering operations north and south of the Angolan capital of Luanda, defense force spokesman twice denied the Angolan allegations.

In his statement, Viljoen defined the role of SADF ``elements'' in Angola as one of gathering information about the African National Congress (ANC), the South West African People's Organisation (SWAPO) and ``Russian surrogate'' forces threatening the safety of South Africa and Namibia. (SWAPO is fighting South Africa for control of Namibia and the ANC, which is believed to have some bases in Angola, is seeking the overthrow of the Pretoria regime.)

Viljoen said: ``At the moment there is concern because contact with . . . a small element has been broken.''

Observers deduced that Viljoen and the Angolans might have been referring to the same unit, although each had attributed different purposes to the SADF's presence.

The latest Angolan allegations came against a background of repeated accusations by Luanda that South Africa actively supports the UNITA rebel forces in Angola. UNITA leader Dr. Jonas Savimbi, like South Africa, wants to force the expulsion from Angola of the Cuban troops buttressing the Angolan government.

Pretoria's high regard for Dr. Savimbi was evident last year when he attended the inauguration of President Pieter W. Botha in Cape Town. The South African Minister of Foreign Affairs, Roelof Botha, is on record as describing Savimbi as a significant factor in the Angola situation. Pretoria believes there can be no political solution in Angola which excludes Savimbi.

Savimbi's insurgent forces have traditionally operated in the southern regions of Angola. But they recently opened up a front in the oil producing north. If South African soldiers have indeed been killed and captured in Cabinda, their presence will inevitably be linked to the new UNITA offensive -- whatever explanations the SADF may offer.