The UN says it is too early to assess the extent of the flood damage in Dar es Salaam [still from youtube]

At least 23 people have been killed in the worst floods to hit the Tanzanian capital, Dar es Salaam in 50 years, officials have said.

"The tragedy has left at least 23 people dead and 4,909 displaced," Said Meck Sadick, Dar es Salaam's regional commissioner told the AFP news agency on Thursday, warning that the death toll could rise.

Businesses were forced to close and thousands were left homeless as the city became inundated with flood water.

"The last time Dar es Salaam recorded such heavy rains was in 1954,"Agnes Kijazi, Tanzania Meteorology Agency director, said at a press conference following the downpour that has hit the city over the past few days.

Philippe Poinsot, Country Director of the UNDP told UN radio that it was still too early to assess the extent of the needs of those affected.

"We are in touch with the government and some other actors like the Red Cross ... We are helping to get a clear assessment of what may be needed.

"[We] probably [need] tents and blankets, some dry rations as immediate assistance, but the [Tanzanian] government is leading the relief effort at this point."

'Unexpected'

UNDP's Poinsot added: "It is always difficult to prepare for an event like this and I dont think Dar es Salaam has seen flooding like this for many many years, so it is quite unusual to see that amount of rain in this particular month. So this was very unexpected.

"From what we have seen the government has been very quick to try and respond [to the crisis]."

Jakaya Kikwete, Tanzania's president, visited several of the camps set up in the city to shelter the flood victims and urged those living in affected areas to leave their homes.

"Floods in these low lying areas have been recurring for years, the lasting solution is to vacate the flood prone areas," he said.

"It is high time that responsible authorities including city planners, mayors and councilors stopped issuing permits for developers to erect structures in such areas," Kikwete added.