Kenya’s military chief Gen Francis Ogolla died in a helicopter crash west of the country, President William Ruto announced on Thursday and declared three days of national mourning.

The helicopter was carrying 11 people, including Gen Ogolla, when it crashed on Thursday and caught fire in a remote area near the border with Uganda, killing nine people onboard, the president said.

It is unclear what caused the crash. However, soon after President Ruto made the announced the death of the military chief during a live television broadcast, social media became awash with speculation about the cause of the accident and death in a banditry-prone region.

Some posts on social media have speculated about assassination as Gen Ogolla was at the centre of a group of senior government officials assembled by retired President Uhuru Kenyatta to overturn election results announced by the electoral commission in favour of Ruto.

President Ruto announced that investigations into the possible cause of the chopper accident and death of the soldiers have commenced.

Gen Ogolla, 61, was on a tour of the country’s troubled western region that has seen frequent attacks by local bandits. He was appointed Kenya’s Chief of Defence Forces in April last year after Gen Robert Kibochi retired.

Political controversy surrounded Ogolla even before his appointment, when he was accused by the country’s electoral commission chairperson as being part of a national security council delegation that tried to influence the outcome of the 2022 general election against President Ruto.

Ruto later explained that he called Gen Ogolla before his appointment and said that, despite the election controversy, he was the most qualified for the job. Gen Ogolla joined Kenya’s military force 40 years ago.

He was a graduate of École Militaire de Paris, the National Defence College of Kenya, Egerton University and the University of Nairobi.

Gen Ogolla is survived by his wife Aileen, two children and a grandson

• a Tell / AP report