Most of the Mozambican refugees in South Africa came from the south of their home country, which is suffering drought and crop failure again this year.

The convoy was reportedly carrying Zimbabwean maize for Mozambican refugees in Malawi.

Because of security concerns, these diplomats say, Zimbabwe recently forcibly repatriated about 2,000 Mozambican refugees and there is concern that the Government might repeat the move.

But more than 300,000 Mozambican refugees are believed to live here and the South African Government is now quietly negotiating United Nations assistance for some.

Zimbabwe, which also has a number of Mozambican refugees, has ordered some of them to leave.

Malawi is facing a severe drought and difficult transport problems, which have become complicated by being host to more than one million Mozambican refugees.

About 1.7 million Mozambican refugees have gone home.

Tongogara camp was established in 1984 to house Mozambican refugees.

In addition, numbers of Mozambican refugees had been repatriated from neighbouring countries.

"We've been spending $35 million to $40 million a year caring for over a million Mozambican refugees for the past eight years," he said.