Two police officers have been shot dead in the northern Kenya town of Garissa, close to the border with Somalia, hours after a child was killed in a grenade attack on a church in Nairobi.
Kenya has been hit by a series of grenade and gun attacks since it sent troops into Somalia last October in pursuit of Islamist al Shabaab militants, whom it blamed for kidnapping its security personnel and Western tourists.
The killing of the police officers and the attack on the church came days after Kenyan troops launched a surprise offensive on the southern Somali port of Kismayu, al Shabaab's last stronghold, forcing the rebels to flee.
Most of the inhabitants of Garissa, where the police officers were shot, are ethnic Somalis and the town is located only 180 km from Kenya's border with Somalia, Reuters reports.
Garissa's deputy police chief Herman Ndiema told Reuters the killers drove up in a taxi to the policemen as they walked along a street, shot them dead and stole their guns.
"We suspect sympathisers of the al Shabaab militant group were behind the attack."
The stolen guns, G3 rifles, were later recovered a short distance from the scene of the attack, a regional administrator said.
Earlier in the day, a nine-year-old boy was killed and three other children wounded when a hand grenade was thrown into a Sunday school session in a church in the capital Nairobi, police and medical staff said.
Police said attackers threw the grenade into the Sunday school service in St. Polycarp's church on Nairobi's Juja Road.
The grenade exploded, spraying the children with shrapnel and fatally injuring the boy.
A police spokesman said he suspected the blast might have been carried out by sympathisers of al Shabaab.