NAIROBI, Kenya (AP) — Five people have been killed in a bomb attack in northern Kenya, the interior ministry said Monday.

The bomb, which exploded in El Wak town in Mandera County, near the border with Somalia, wounded five other people. There was no immediate claim of responsibility, but Somalia-based al-Shabab militants affiliated with al-Qaida have carried out other attacks in the area.

The bomb had been placed on a donkey cart to avoid detection, the interior ministry said.

Earlier this month, gunmen suspected to be al-Shabab entered the El Wak hospital and injured guards while asking about the whereabouts of doctors. No arrests were made.

Al-Shabab often carries out cross-border attacks, especially in the remote Kenyan counties of Mandera and Garissa.

The extremist group has threatened Kenyan forces over their yearslong deployment to Somalia as part of multinational efforts to stabilize the Horn of Africa nation following more than three decades of conflict.

The African Union Transition Mission in Somalia is set to end in December, leaving Somali forces largely responsible for security.