Nairobi - Two people shot when attackers sprayed a Kenyan church with gunfire on Sunday have died of their wounds, taking the total killed in the attack to six, government officials said on Monday.
The attack, in the Likoni district near the port city of Mombasa, came amid heightened warnings of a threat of Islamist violence in Kenya and despite boosted security in major cities.
"Two more victims succumbed last night, we still have 15 others admitted in hospital," local ministry of health chief Khadija Shikely said.
Some of those wounded were young children.
No group has claimed responsibility, but Kenya has been hit by a series of attacks since sending troops into southern Somalia in October 2011 to battle al-Qaeda-linked Shabaab insurgents.
Local police chief Robert Mureithi said Monday that around 100 suspects had been taken in for questioning following the attack, but that the "main culprits are still at large".
Kenyan troops, which have since joined the African Union force in Somalia, are taking part in a fresh offensive launched this month against Shabaab bases.
The attack on the church comes six months after Shabaab commandos carried out the September massacre in Nairobi's Westgate mall in which at least 67 people were killed.
Home-grown groups including the Islamist Al-Hijra group, a radical organisation formerly known as the Muslim Youth Centre, operate on Kenya's coast and have been linked to the Shabaab.
Several senior Muslim leaders have been gunned down on the coast, with their supporters accusing the police of state-sponsored assassinations - claims the security forces deny.