President William Ruto has condemned the death of a man while in police custody, which has sparked widespread anger.

Police had initially said that Albert Ojwang, arrested over social media posts accusing a police deputy inspector-general of corruption, had died in his cell after hitting his own head against the wall.

But medical examiners said on Tuesday that suicide was unlikely.

“This tragic occurrence, at the hands of police, is heartbreaking and unacceptable,” Ruto said.

He urged the police to cooperate fully to facilitate a “swift, transparent and credible investigation”.

“I fully expect that the truth about what happened to Ojwang will be established in due course and that justice will be served,” he added.

Ojwang’s death comes with Kenya on alert as it marks a year since massive protests over tax rises and corruption.

A government pathologist, Bernard Midia, one of five to examine Ojwang’s body, told reporters on Tuesday that the injuries were “unlikely to be self-inflicted”.

The case has sparked anger online and small protests in the capital Nairobi.