At least 17 people were killed and dozens of others were injured as heavy rains triggered building collapses across war-torn Sudan.

"The number of victims has risen to 17," said an employee at a hospital in Abu Hamad, a small town in Sudan's River Nile state, some 400 kilometers (nearly 250 miles) north of the capital Khartoum.

"The power is out in the city and people are spending the night out in the open, dreading more rainfall," they said, requesting anonymity because they were not authorized to speak to the media.

Some 11,500 homes have already collapsed, the state's Infrastructure Minister Samir Saad told reporters Tuesday, and at least 170 people have been injured.

Each year in August, peak flow on the Nile is accompanied by torrential rains, destroying homes, wrecking infrastructure and claiming lives, both directly and indirectly through water-borne diseases.

The impact is expected to be worse this year after more than 12 months of fighting that has pushed millions of displaced people into flood zones.

"Heavy rains caused most of the houses to collapse and all the shops in the market collapsed," a witness in Abu Hamad told AFP by telephone.

Last week, a flash flood caused the deaths of five people in Port Sudan, on the Red Sea coast.

Since July 7, torrential rains and flooding have killed more than 30 people across the country, Sudan's federal emergency operations center said Tuesday.

According to the United Nations, rain and flooding have displaced more than 21,000 people since June – mostly in areas already reeling from heavy fighting.

Aid groups have repeatedly warned that humanitarian access, already hampered by the war, is now being made near-impossible in remote areas as roads flood.

Sudan faces what the United Nations has called the world's worst humanitarian crisis in recent memory, as fighting between the army and the paramilitary Rapid Support Forces shows no sign of abating.

More than 10 million people have been forced from their homes, while the main battlegrounds teeter on the brink of all-out famine.

The war has already pushed the nearly half a million residents of the Zamzam camp outside the besieged Darfur city of el-Fasher into famine, a U.N.-backed assessment said last week.