Kenyan medical examiners said on Tuesday that suicide was unlikely in the death of a man while in police custody – a case that has sparked protests and widespread anger.

Albert Ojwang, 31, was arrested over posts on social media accusing police Deputy Inspector-General Eliud Kipkoech Lagat of corruption.

Police initially said he died over the weekend in his cell after hitting his own head against the wall.

But government pathologist Bernard Midia, one of five to examine Ojwang's body, told reporters the injuries were "unlikely to be self-inflicted."

'Cause of death very clear'

Ojwang was arrested in Western Kenya but transferred more than 350 kilometres to Nairobi, "without proper orders from the court", the Law Society of Kenya (LSK) said on Monday.

Kenya was already on edge as it marks a year since massive protests over tax rises and corruption that triggered a police response in which at least 60 were killed.

"The cause of death is very clear; head injury, neck compression and we also have other injuries spread all over the body that are pointing towards assault," Midia said.

His colleague, Geoffrey Mutuma, said there were "a lot of injuries in the skin, in the back... inflicted with a lot of force."

'Main suspect'

Ojwang also had "what we call self-defence injuries", he added.

After the postmortem, protesters marched to the deputy inspector-general's office, demanding his immediate resignation.

"The results were coinciding well with our argument that Albert Ojwang was murdered in central police station," activist Geoffrey Mboya told AFP.

The protesters have described the deputy inspector-general as "the main suspect."

'Heavy burden for my family'

"We want Eliud Lagat to resign...so that investigations can be done properly," activist Shakira Wafula said.

Five officers have been removed from active duty to "allow for transparent investigations", police spokesperson Michael Muchiri said on Tuesday.

He said the "suicide theory has been banished" after the postmortem results.

"This is a heavy burden for my family," said the victim's father, Meshack Ojwang.

'Horrifying long list'

Veteran opposition leader Raila Odinga wrote on X that Ojwang "joins the horrifying long list of young and defenceless Kenyans whose lives have been taken too soon, in brutal and senseless circumstances, at the hands of the police."

Rights groups say dozens were illegally detained in the aftermath of last year's protests, with many still missing, and others have been arrested for mild criticism of the government and President William Ruto.

Odinga, who forged an alliance with Ruto's government this year, said the deaths "seriously erode the authority and credibility of the police and the state."