garissa school attack memorial
People sing as they attend a memorial concert at the "Freedom Corner" in memory of the Garissa university students who were killed by gunmen in Kenya's capital Nairobi April 14, 2015. Reuters/Noor Khamis

Several Kenyan police officers were killed in a suspected al-Shabab attack Monday night in Garissa county in the country's northeast, local media reported Tuesday. A police spokesman reportedly said that 13 others were missing after the overnight ambush close to the Somalia border.

At least 20 officers were feared dead in Yumbis village, located about 200 miles east of the capital Nairobi, the Associated Press reported, citing the Daily Nation, a local newspaper. Authorities reportedly said that the officers were attacked near the village, about 80 miles northeast of Garissa, close to the scene of last week’s clash between al-Shabab militants and Kenyan security forces.

"There was an ambush on officers who were on patrol and as a result, 13 officers are missing," police spokesman George Kinoti said, according to Agence France-Presse. "Two others sustained injuries and have been taken to hospital.

"More police officers have been dispatched to look for those missing and the attackers," he reportedly said.

Last month, al-Shabab claimed responsibility for an attack at a college in Garissa county that killed 142 students and six security forces, following which the Kenyan government launched an offensive against the militant group.

Al-Shabab is a Somalia-based terrorist group that has been carrying out deadly attacks in the country in an attempt to oust the Western-backed Somali government. It has also launched attacks in neighboring countries, such as Kenya, which support the Somalia government in its fight against the Islamist group.