When the policemen came for Albert Ojwang - the Kenyan blogger whose death in custody sparked protests this week and prompted a rare acknowledgement of police brutality by the president - his wife initially thought he would be safe.

Authorities in Kenya have arrested a senior police officer responsible for the cell where a blogger died, leading to widespread protests in the capital, Nairobi, that left dozens injured.

Demonstrators take to the streets in Kenya's capitol over the suspicious death of a popular blogger in police custody — a flashpoint of outrage in a country still reeling from last year's deadly crackdown on anti-tax protests.