There were protests at the Central police station in Nairobi on Sunday after a teacher died in police custody after his arrest in Migori town.
Detectives are investigating circumstances under which he died.
The teacher identified as Albert Ojwang was arrested on Saturday over X posts he had made.
He was driven to Nairobi and booked at the Central police cells by a team of detectives from Directorate Criminal Investigations headquarters for grilling.
Police said Ojwang died by suicide.
He was alone in a cell when he was found with serious head injuries he inflicted on himself, police said.
He was rushed to Mbagathi Hospital where he was pronounced dead.
Nairobi Police boss George Sedah said the victim injured himself in custody.
“He had injured himself in the head and was rushed to hospital where he died.
He did not die in custody,” said Sedah.
Ojwang was a teacher in Voi and had just traveled to Migori to visit family when he was picked up.
The body was moved to the mortuary pending autopsy. His friends camped at the station seeking explanation into the incident.
A team of detectives from Independent Policing Oversight Authority was expected at the station to join the probe.
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