The bodies of dozens of Ethiopians, believed to be illegal migrants, have been recovered from Lake Malawi after
their overcrowded boat capsized earlier this week, police have said.

"As of today, 47 bodies have been recovered," Malawi police spokesman Davie Chingwalu told the AFP news agency on Thursday, adding that they had been buried in mass graves "because the bodies had decomposed".

Chingwalu said the accident is believed to have happened on Monday night, but only came to light on Tuesday morning when villagers and police "saw dead bodies floating on the lake and a boat floating upside down".

Search operations are still under way for more bodies or possible survivors, the spokesman said.

Chingwalu said Malawians owned the boat used by the migrants as they attempted to cross the lake which straddles the border between Malawi and Tanzania.

"We believe the boat capsized due to overloading, and three Malawians have been arrested for aiding the operation with unknown Tanzanians," he said.

Hundreds of Ethiopians, helped by a syndicate of Malawians, illegally enter Malawi every year from Tanzania through the porous border around the northern town of Karonga.

Most are hoping to make their way to South Africa, the regional economic powerhouse.

In 2007, scores of Ethiopians were discovered in Malawi hidden in an oil tanker on their way to South Africa through Mozambique.