A suspected remote-controlled bomb tore through a predominantly Somali neighbourhood in the Kenyan capital Nairobi on Wednesday, wounding up to nine people during the evening rush hour.
Ambulance sirens wailed through the city's congested streets and a Reuters witness at the scene saw pools of blood on the ground. The victims had been swiftly moved from the blast site.
Kenyan authorities have blamed Somali militants and their sympathisers for a wave of grenade and gun attacks in Kenya after Nairobi sent soldiers into neighbouring Somalia last year to drive out Islamist fighters with links to al Qaeda.
Moses Ombati, Nairobi's police chief, said it appeared the bomb had been planted near a trader's kiosk earlier in the day.
"We think it was detonated by remote control," Ombati said by phone from the blast site where plastic household utensils littered the ground.
The attack appeared to target Kenyan nationals in Eastleigh, a rundown part of the city where there is widespread resentment towards the Somali immigrants who run many of the local businesses.
Nine people were wounded in the blast and three of those victims were in a critical condition, the Kenyan Red Cross said on the social media site Twitter.
An angry crowd pressed against a police cordon and demanded that Somalis, many of whom fled years of fighting in their home country to settle in Nairobi, leave the city.
"Why is this happening to the local people and not the Somalis. Let the police leave this place and we'll sort it out," said one Eastleigh resident who did not give his name.
The explosion could be heard several kilometres away in Nairobi's central business district. There was no immediate claim of responsibility for the attack.
Last month, a grenade attack on a bus in Eastleigh that killed nine people triggered a day of street battles between Kenyan nationals and Somali Kenyans and their ethnic kin.
Mounting insecurity is a growing concern as the region's biggest economy prepares for a presidential election in March - the first poll since a contested 2007 vote which unleashed nationwide ethnic violence.