A protester has died during clashes between police and a group which wants independence for the Coast region around Mombasa.
A member of the Mombasa Republican Council (MRC) died after being hit on the head by a stone thrown by a fellow protester, police say.
Police fired tear gas to prevent about 100 MRC members from entering a Mombasa court.
The court is hearing a challenge to a ban on the group.
The MRC argues that the mainly Muslim Coastal region has been ignored by the national government in Nairobi.
Prime Minister Raila Odinga this week rejected holding talks with the MRC, saying it must first drop its demands for independence.
Dozens of MRC members have been arrested in recent days, local media report.