Explosions in Kenya's capital have killed at least five people and critically injured nine others, the national Disaster Operations Centre said. 

Monday's attack in Nairobi's Eastleigh area, sometimes called "Little Mogadishu", might have involved twin blasts, the country's police commander Benson Kibui told Reuters news agency.

An Associated Press reporter at the scene said at 7:30pm local time there were two blasts about 200 metres apart. One of them caused the first floor walls of a restaurant to collapse and appeared to be caused by a device larger than a grenade.

"Police are securing the area for emergency response services," the disaster organisation said on its official Twitter account.

Ambulances and private cars ferried the injured to hospital, a witness told Reuters.

There was no immediate claim of responsibility. In the past, such attacks in the area that is popular with Somalis have been blamed on Somalia's al-Shabab armed group.

Monday's blasts came a day after a man suspected of assembling a bomb was killed when it went off where he lived near Eastleigh, Kenyan newspapers reported. 

The Standard  newspaper, which cited police and witnesses, said three men who lived with the victim fled in a car shortly after Sunday's blast.

Source: Agencies