Kenya's government has sent a team to investigate the helicopter crash that killed military chief Gen Francis Ogolla and nine others.

It was not immediately clear what caused the crash.

Gen Ogolla was among 12 occupants of the military aircraft that went down on Thursday afternoon shortly after take off in the north-west of the country.

The bodies of those who died were flown to Nairobi and the two survivors are being treated in hospital.

The four-star general will be buried on Sunday at his home in western Siaya county, his family has said.

Announcing three days of national mourning, President William Ruto said the deaths were a "moment of great sadness" for the country.

Gen Ogolla was appointed Kenya's Chief of Defence Forces in April last year.

Mr Ruto described his chief military adviser as a gallant officer who had died in the line of duty.

"Our motherland has lost one of her most valiant generals, gallant officers, service men and women," Mr Ruto told the nation.

Gen Ogolla first joined the Kenya Defence Forces on 24 April 1984, according to the Kenyan defence ministry's website.

He was due to mark 40 years in the military next week.

He began his career as a 2nd lieutenant in the country's air force, where he trained as a fighter pilot with the US air force, the ministry says. The late general also trained in imagery intelligence, counter-terrorism and accident investigation.

In 2018, he became commander of the air force.

In an interview last May, Mr Ruto said he appointed Gen Ogolla as the army chief "against the advice of many people". The president said Gen Ogolla was among a group who tried to influence the 2022 presidential election results.