MOSCOW -- South Africa, backed by Washington, has stepped up its military incursion into Marxist Angola and bombed a southern city with highly toxic nerve gas, Soviet and Angolan officials charged Thursday.
'The South African military, spreading their criminal armed aggression against the young African republic and grossly violating international agreements, are using chemical weapons, specifically highly toxic nerve gas,' the official Soviet news agency Tass said.
'South African planes used this barbarous weapon when bombing the South Angolan city of Cuvelai, Cunene Province,' Tass said.
The Marxist Angolan government issued a similar report and warned it might call on Cuban forces to help fight the offensive launched by South Africa in early December against Angolan-based South West African People's Organization guerrillas.
Angola made similar charges of chemical warfare in early November.
At the United Nations, the Security Council met to condemn South African armed attacks in southern Angola and to demand an immediate withdrawal of Pretoria's troops from the country.
The SWAPO guerrillas are fighting a 16-year bush war against Pretoria's rule over mineral-rich South West Africa, or Namibia, which lies between South Africa to the southeast and Angola to the north.
An estimated 105,000 South African troops occupy South West Africa, and Pretoria also backs anti-communist guerrillas of the Union for the Total Independence of Angola fighting the Angolan government.
Angola's Marxist government is backed by 30,000 Cuban troops and advisers and receives military aid from the Soviet Union, Western experts say.
An earlier Tass report said the aggression could not have occurred without Washington's support and encouragement and 'cannot be left unpunished.'
The news agency said the world was outraged by the actions -- except Washington, which 'keeps mum about the use of chemical weapons' because they are developed under licenses from the United States and other NATO countries.
The official Angolan ANGOP news agency, monitored in Lisbon, Portugal, said South African forces bombarded 'Angolan troops and civilians' in Cuvelai, but did not specify when the alleged attacks took place or describe the nature of the chemical weapons. Casualties were not mentioned.
South African warplanes bombed government positions Tuesday in Lumbala, 180 miles from the Namibian border and situated in the eastern portion of Angola, de Figueiredo said.