Flooding kills more than 120 in DR Congo capital

More than 120 people were killed as the worst floods in years battered DR Congo's capital Kinshasa following an all-night downpour, authorities said in a provisional assessment.

Major roads in the centre of Kinshasa, a city of some 15 million people, were submerged for hours, and a key supply route was cut off.

The death toll -- which was first estimated in the late afternoon to be at least 55 -- jumped to more than 120 by nightfall.

The government has announced three days of national mourning beginning, according to a statement from Prime Minister Jean-Michel Sama Lukonde's office.

A major landslide occurred in the hilly district of Mont-Ngafula, smothering National Highway 1, a key supply route linking the capital with Matadi, a port further down the Congo River and a crucial outlet to the Atlantic Ocean.

The highway should be reopened to small vehicles within the next day, but it could take "three or four days" for trucks, the prime minister said.

The streets of the up-market Gombe district -- home to government buildings and usually spared the problems affecting other areas of Kinshasa such as inadequate waste disposal and power supplies -- were also inundated.

Many dwellings are shanty houses built on flood-prone slopes, and the city suffers from inadequate drainage and sewerage.