Clashes broke out on Monday in a predominantly Somali district of Nairobi between people of Somali nationality or origin and other Kenyans, leaving several people wounded, a police chief said.
The clashes broke out at the site where a bomb went off on a bus on Sunday, killing seven and wounding many more.
An AFP reporter at the scene said police used tear gas and fired into the air to contain the violence, which started when non-Somali Kenyans turned on Somalis and attacked their shops and stalls, accusing them of being responsible for the bus bomb.
"There is chaos. Several people have been injured but we are doing everything possible to contain the riots," Moses Nyakwama, Nairobi Police chief told AFP by phone.
Eastleigh, the Somali district of Nairobi, has in recent weeks been the scene of several attacks, mostly blamed on sympathisers of Somalia's Al-Qaeda-linked Shebab fighters.