As the waters rise, thousands are abandoned to look in vain for help

South African army helicopter crews raced against the clock to save the lives of hundreds of stranded Mozambicans on Tuesday but had to abandon thousands of others to their fate, clinging to rooftops and trees as flood waters rose quickly around them.

South African army helicopter crews raced against the clock to save the lives of hundreds of stranded Mozambicans on Tuesday but had to abandon thousands of others to their fate, clinging to rooftops and trees as flood waters rose quickly around them.

As the shocking scenes were broadcast around the world, the UN made a desperate appeal for helicopters and boats while politicians in the West bickered over the slow reaction to the crisis. Britain chartered two more aid helicopters and increased its cash contribution to £3m.

Along the flooded Limpopo river, helicopter engines whined into life, racing to rescue mothers with babies clinging to their backs and other victims trapped in the floods. But even the clatter of an approaching helicopter did not mean imminent rescue for the victims of the worst floods Mozambique has seen in living memory.

Pilots reduced to tears reported seeing stranded people desperately waving T-shirts and stalks of maize to attract their attention. But, despite the duration of the two-week-old crisis, there are still less than 12 helicopters operating in this vast country.

There were heart-breaking scenes, as South African air force crews fought off desperate people who were trying to board fully loaded aircraft.

In one dramatic episode a woman threw her baby at a full helicopter as it lifted off. A crew member caught the child by its arm, saving it from certain death, but it was unclear whether the mother survived. Buildings were also seen collapsing under the weight of people minutes before they were going to be rescued.

The South African Air Force has rescued 8,000 people since the latest deluge of water arrived on Sunday, but aid workers say that at least 100,000 still need rescuing.

"This is an absolute disaster. Simply unbelievable. There are no words to express the level of destruction." a veteran, combat-hardened South African pilot told Reuters news agency.

In the coastal town of Xai-Xai, north-east of the capital, Maputo, a wave of water coursed down the flooded Limpopo river, submerging the entire town on Monday night. With helicopters busy rescuing people elsewhere, three or four rubber rafts collected people from Xai-Xai rooftops, but could transport only a half-dozen people to safety in each trip. By yesterday evening, hundreds of others were still stranded on rooftops, inches above the flood waters. Drowned cattle floated among the clusters of survivors. Nobody knows how many people died as the river swept through Xai-Xai, but aid workers said the survivors could be swept away when the Limpopo surges further today.

"The situation in the Limpopo Valley is worsening," President Joaquim Chissano said after he flew over Xai-Xai and other areas of the country, which were submerged in muddy water. He described seeing bodies floating in flooded rivers.

"Only helicopters can help people who are hanging on the top of the houses. There are people who are on the roofs of huts, in the trees waiting for rescue," he said. "We call for air force helicopters to see what they can do today, because if they don't do it today there will be a loss of life. This evening there will be no more roofs."

Further upstream, about 22 miles south-west of Chokwe, hundreds of people were still stuck in trees and on rooftops yesterday after floods hit early Sunday morning. "If they are not reached today there will be a loss of life."

Further upstream about 22 miles south west of Chokwe hundreds of people were still stuck in trees and on rooftops yesterday after floods hit early Sunday morning. South African helicopters hoisted loads of about 25 people each to safety, but the process was painfully slow as people struggled to get to the helicopters.