A grenade blast in Kenya's capital Nairobi has killed one person and wounded others, local media reported.
Police also said they were investigating Friday's blast, which occurred in the Somali-dominated area of Eastleigh near an air force base, Wilfred Mbithi, an assistant police commissioner, told the Reuters news agency.
The blast injured six people, according to Daily Nation, Kenya's leading daily.
No group claimed responsibility for the blast that came on the eve of a visit by Hillary Clinton, the US secretary of state, to Nairobi, police said.
Clinton, on an 11-day, seven-nation Africa tour, is due to travel to Kenya on Saturday, where she will meet with Kenyan leaders and officials from Somalia's government, which is preparing to end its mandate later this month.
Kenya has suffered a spate of grenade attacks, shootings and bomb blasts since sending troops into southern Somalia in October to crush Islamist bases there, prompting warnings of revenge attacks by the al-Qaeda linked fighters.
In June, attackers in the border garrison town of Garissa carried out Kenya's worst attack in a decade, when they targeted worshippers as they held Sunday prayer service, killing 18 people.
Somalia's weak and Western-backed transitional government is due wrap up on August 20 after eight years of infighting and minimal progress, to be replaced by a new system chosen through a United Nations-backed process.
Nairobi's Eastleigh district is home to thousands of Kenyan ethnic Somalis, as well as Somalis who have fled more than two decades of war in their nation.