CAPE TOWN, South Africa -- The Berlin-born commander of South Africa's secret naval dockyard at Simonstown and his wife have been arrested on charges of spying for the Soviet Union, Prime Minister Pieter Botha said Wednesday.
Commodore Dieter Gerhardt, 47, and his wife Ruth, 40, were arrested 'a few days ago' for questioning under the Internal Security Act, Botha said.
Government sources said Gerhardt was a 'highly trained KGB agent' who attracted the attention of security forces by his lavish lifestyle and by traveling abroad extensively in violation of military regulations.
The sources said Gerhardt spent heavily on Persian carpets and silverware.
Gerhardt is the first South African citizen known to have been detained on espionage charges since World War II.
Since the early 1970s two Soviets have been arrested for spying in South Africa.
One of them, Maj. Alexei Koslov, was released late last year in a complicated exchange deal involving several unidentified Western agents held by Moscow and prisoners of war in Angola, including American mercenaries captured during the 1975-76 civil war.
Botha said the South African security services had launched a high-level investigation into the Gerhardts' activities but gave no other details.
Defense sources said Gerhardt would have detailed knowledge of South African naval operations including the movement of its three French-built Daphne class hunter killer submarines which are frequently used to track Soviet shipping around the Cape sea routes.
The Soviets have increasingly used the Cape route to reinforce and resupply its growing Indian Ocean fleet.
South Africa is thought to share intelligence on Communist bloc shipping with the West despite an international arms embargo slapped on Pretoria in 1977 by the United Nations.
Britain once held the Simonstown base -- thought by some naval strategists to be the only base capable of defending the Cape sea routes - but relinquished control in 1957.
A submarine complex incorporating an operations center alongside a marine elevator capable of docking all South African warships except a large tanker was opened at Simonstown in July 1972. A new maritime headquarters was opened at Silvermine in March 1973.
In 1975, Britain's then Labor government terminated the Simonstown agreement under which Royal Navy and other 'friendly' warships used the base's facilities.
During the Falklands war last year, many defense specialists agreed Britain would have been better placed to counter the Argentine invasion more quickly if it had retained its Simonstown operations.