Kenyan officials say search teams are looking for three Ugandan military helicopters that went missing in central Kenya.

Bad weather is hampering rescue efforts in the Mount Kenya area, but officials say the pilot of one of the helicopters has made radio contact.

The helicopters are part of a force Uganda is sending to bolster African Union peacekeepers in Somalia, who are battling al-Qaida-linked al-Shabab rebels.

A fourth helicopter landed safely at a Kenyan military base in the northern town of Garissa.