By Steven Swindells
JOHANNESBURG, Feb 14 (Reuters) - The death toll from the worst flooding across southern Africa in nearly 50 years rose to at least 45 on Monday as more rain deluged the region.
South African police said at least 45 people had been killed, but the number was expected to rise as rescuers reached remote areas. Thousands have been left homeless after nearly a week of constant rain.
President Thabo Mbeki declared parts of the country's Northern and Mpumalanga provinces disaster areas as first estimates put the cost of the flooding at more than one billion rand ($159 million).
The South African Insurance Association has estimated its members could receive claims totalling 300 million rand, but the figure could change once claims had been finalised.
In Mozambique, an estimated 250,000 people have been forced into temporary shelter and fertile farming land in the Limpopo Valley has been heavily damaged.
Counting in Zimbabwe's controversial referendum on a new constitution was delayed after heavy rains rendered some roads impassable while in neighbouring Botswana dams overflowed.
South African police warned that areas most affected by recent flooding would have to endure more rain, and said they expected the death toll to rise.
"The rain has started again. We have advised people to evacuate low-lying areas. Police and the army are helping in the evacuation," Northern Province police spokeswoman Ronel Otto told Reuters.
Northern Province, where 26 have died because of flooding, was the worst hit part of South Africa. Fields and residential areas were flooded as rivers burst their banks.
ILLEGAL MIGRANTS DROWN
The latest deaths occurred on Monday when two Zimbabweans seeking to enter South Africa illegally from Botswana were swept away trying to cross the Limpopo, Otto said.
Towns and villages around the Levubu River area and farm land in the Rooi Bokkraal areas were the most vulnerable to more flooding, he added.
The South African Weather Bureau forecast thunderstorms and showers for the Northern Province at least until Friday.
In Mpumalanga province, the official death toll stood at 15 but this was expected to rise, a police spokesman said. Rain was forecast to continue in the province until Thursday.
The rains have also led to drownings and traffic chaos in the commercial capital, Johannesburg. South Africa's transfusion agency made an urgent appeal for blood as donors were kept away by the rain.
In neighbouring Mozambique, an estimated 100,000 people were estimated to have been displaced in the capital Maputo, where fears were growing of malaria and cholera.
There has been no official report of deaths in Mozambique, where the South African air force deployed rescue helicopters. Both former colonial power Portugal and the U.S. embassy in Maputo provided relief funds.
A huge floodwave hit the district of Chokwe at the weekend, damaging the fertile rice and maize growing farmland of the Limpopo Valley in the southern province of Gaza.
On Sunday, the flood peak hit the Chibuto district further downstream, cutting off villages including Malehice, the home village of President Joaquim Chissano.
State officials have hastily removed equipment from government buildings in the provincial capital Xai-Xai.
"If the river continues to rise, the waters could invade the city," said Adriano Chivango of the National Disaster Management Institute.
In flooded areas of Maputo province, an estimated 10,000 people were cut off from the rest of the country. Mozambique's main north-south highway was impassable at Manhica.