Up to seven gunmen attacked two churches in Garissa, Kenya, on July 1. Around 50 others are thought to have been injured in the attacks.

The attackers killed two armed police officers, who were posted outside churches following previous attacks, before targeting worshippers inside one Roman Catholic church and one Africa Inland Church.

The Red Cross flew the three most critically injured victims by air ambulance to Nairobi. Three children were reported to be among the murdered churchgoers.

"It is a terrible scene, you can see bodies lying in the churches," said regional police chief Leo Nyongesa.

Kenya has suffered a spate of gun, grenade and bomb attacks since sending troops into southern Somalia last October to target Shebab rebels who are fighting to overthrow the UN-backed government.

Pro-Shebab Twitter site Al-Kataib later referred to a "successful operation in Garissa", but did not specifically claim responsibility.