Dozens shot dead in Kenya bus attack

Gunmen have attacked a bus and killed at least 28 eight passengers who were heading to the Kenyan capital Nairobi from Mandera in the country's northeast, officials and local media said.

The interior ministry confirmed Saturday's attack, saying via its official Twitter handle: "Bandits ambushed a bus from Mandera that was heading to Nairobi at dawn and killed 28 passengers of the 60 that were in the bus."

"Security agencies are in pursuit of the criminal gang. We'll give a comprehensive update once preliminary reports are out." 

The attack happened at 5:45am local time when the bus had covered 8km of the journey.

Quoting Mandera County Commissioner, journalist Boniface Mungeri said the attack was carried out by "about 100 gunmen who commandeered" the bus and forced the passengers out.

Mungeri said the passengers were separated into groups according to their religion. Non-Muslims, the reporter said, were executed and Muslims were freed. The assailants attempted to take the bus but it got stuck in mud on the unpaved road.

Among those killed were two security officers and teachers who were travelling to their home towns on holiday, said the reporter.

Kenyan authorities have previously blamed the Somali armed group al-Shabab for a wave of deadly attacks. Mandera shares a border with Somalia, where Kenya sent troops in 2011 after raids on its coastal towns blamed on al-Shabab.

Al-Shabab has also been blamed for the September 2013 attack on the Westgate shopping mall, which killed 77 people.