At least 48 people were killed when a truck lost control and ploughed into other vehicles and pedestrians at a busy junction in western Kenya on Friday, police said.

Television images showed scenes of devastation at the site of the crash, with the mangled wreckage of several minibuses and the overturned truck as rescue workers hunted in darkness for people feared trapped.

"So far we can confirm 48 dead and we are suspecting one or two are still trapped under the truck," local police commander Geoffrey Mayek told AFP after the accident on the highway between the towns of Kericho and Nakuru at around 6:30 pm (1530 GMT).

He said another 30 people had been seriously injured and rushed to various hospitals, warning that the toll could rise.

Kenyan leaders including President William Ruto expressed their condolences after the accident, which took place at a busy area known as Londiani junction.

The Kenyan Red Cross, which sent ambulances and rescue workers to the scene, said heavy rains were hindering rescue operations.

"The truck was on high speed and it was hooting. It tried to avoid several vehicles before it came straight into the market," said witness Jepkoech.