At least six people have been killed in explosions in the Kenyan capital, Nairobi, officials say.

Several people were also injured in the blast, which took place in the Eastleigh suburb of the city.

Eastleigh is known as "Little Mogadishu" because it has a large Somali population.

"Police are securing the area for emergency response services," said the Kenya National Disaster Operation Centre.

The cause of the blast is unknown but there have been several grenade attacks in Eastleigh, including one in December last year that killed four people.

Although no group said it was behind that attack, many blamed it on the Somali militant group al-Shabab.

Four members of the group were behind the four-day siege at a shopping centre in Nairobi last September, in which 67 people died.

The militants had stayed in Eastleigh before launching the attack.

Kenya has several thousand troops in Somalia, helping the UN-backed government tackle al-Shabab, who are linked to al-Qaeda.