At least seven people were killed in an overnight devastating flood in Somalia's capital Mogadishu, local government officials said on Saturday.

Torrential rains, which started on Friday night and lasted about 10 hours, touched off the floods that displaced more than 200 families.

Nine houses were completely destroyed across various districts of Mogadishu, while six major tarmac roads were also damaged.

"Seven people died, two of them women," Salah Omar Hassan, the spokesman of the Banadir regional administration, said at a press conference.

Hassan added "The floods also swept through the houses of 200 families while destroying six key tarmac roads, which are very important for the movement of transport and people in the capital Mogadishu."

Abdullahi Ali, a 35-year-old father, said that two children died in houses in his neighbourhood, saying, "I have never seen rain this heavy in Mogadishu."

"It continued for more than ten hours, and in my neighbourhood, several houses were destroyed," Ali said.

Another resident, Fadumo Ali, said people were trapped in their homes after the heavy rain caused widespread havoc.

A UN report published on April 30 revealed that more than 45,000 people have been affected by flash floods in Somalia since mid-April. (AFP)