A bus damaged after an explosion is seen along the Thika super-highway in Kenya's capital Nairobi, May 4, 2014.
NAIROBI - Bomb attacks against two buses along a busy highway in the Kenyan capital Nairobi on Sunday left at least 27 people wounded, some with serious injuries, police said.
The Nation newspaper, quoting medical officials, reported two people had died of their injuries, and that the 45-seater buses were almost completely full when the bombs went off.
"In both incidents 27 people have been taken to hospital with injuries. Six of them have serious injuries," said a police officer at the scene, adding: "We are still checking with hospitals because people were taken to hospital by samaritans."
Some Kenyan media reports said that explosive devices, possibly powerful grenades, may have been thrown at the buses from the side of the road, although others said bombs may have been planted inside the buses.
The bombings came the day after twin attacks in the restive port city of Mombasa, including a grenade attack on a bus, which killed four people and wounded around 15 others, and a bombing outside a luxury beach hotel.
The buses blew up along the Thika Road highway, an area around eight kilometres northwest of Nairobi&39;s city centre.
An AFP reporter at the scene saw a red passenger bus with a large hole in its side, and with the ripped panels spattered in blood. Kenyan media also showed images of a green bus with its roof and sides buckled by an explosion.
There was immediate claim of responsibility for the attacks -- although Kenyan authorities are currently engaged in a major security crackdown on suspected supporters of neighbouring Somalia&39;s Al-Qaeda-linked Shebab rebels.
Both Nairobi and Muslim-majority Mombasa, a port city that is one of the main gateways to east Africa as well as a popular tourist destination, have been hit by sporadic unrest in recent months.
Kenya has been targeted by Shebab since sending troops to war-torn Somalia in 2011. Kenyan soldiers are still posted in southern Somalia as part of an African Union force supporting the country&39;s fragile internationally-backed government.
The Islamist group claimed responsibility for the high-profile attack on Nairobi&39;s Westgate shopping mall last year in which at least 67 people were killed.