Three suspected al-Shabab militants have been killed after they attacked a police camp in Kenya's eastern County of Garissa, close to the border with Somalia, police say.

Other fighters were repulsed by security officers, a statement said.

At least eight Kenyan police officers were killed in an al-Shabab bomb attack last week in north-eastern Wajir County.

The militants have been trying to overthrow the Somali government.

The al-Qaeda-linked group has carried out attacks and kidnappings in Kenya, vowing retribution for the country's involvement with Amisom - a 20,000-strong African Union force helping to support the government in Somalia.

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The Friday night attack happened in Yumbis Border Patrol unit camp in Fafi sub-county, but security officers did not suffer any casualties, police said.

The militants damaged a mobile phone mast, cutting off communication in the area, local newspaper The Star reports.

A team of security forces was pursuing the surviving assailants, police said. (BBC)