But they have vowed on Sunday to respond through prayers, not violence.

In the port city of Mombasa security guards body-searched worshippers, while in the eastern town of Garissa, where attacks on two churches last week killed 17 people, military police patrolled the streets and Muslims came out in a show of solidarity.

Both Christian and Muslim leaders have urged calm this week, keen to prevent the grenade and gun attacks in Garissa last Sunday driving a wedge between the two largest religious communities and triggering violence.

“Why would they attack a church on a Sunday? Remember the recent one in a Nairobi church and several others...all on Christians. Are you telling me that is a coincidence? No way,” said Margaret Wakio, 28, clutching a bible and hymn book as she entered church in Mombasa.

“This is intentionally targetting us. We will fight back, but through prayers not weapons,” she said.

Mombasa, Garissa and towns along the border with Somalia, all predominantly Muslim areas, have been subjected to a wave of violence since Kenya sent troops into its war-ruined neighbour to help crush al Qaeda-linked rebels.

Muslims and Christians alike have been killed.

Last Sunday’s coordinated assault by masked assailants resembled the tactics of Nigeria’s Islamist militant group Boko Haram which has killed hundreds of people in sectarian violence on the other side of the continent.

In a village church north of Mombasa, nervous heads in the congregation turned anxiously each time the door creaked open.

“Let us be calm. Let us not fear. Let us not grumble, complain and blame each other,” Pastor Antony Mramba preached.

“We will go down on our knees and cry to our father in heaven, for no weapon hurled against the righteous shall prosper.”

Heightened security

In Garissa, a market centre for trade in camels, donkeys, goats and cattle about 200 km (120 miles) from the Somali border, armed military police and plain clothed security agents swarmed through the dusty streets.

Kenya’s police, previously criticised by rights groups for arbitrary detentions in the aftermath of attacks, arrested more than 30 people after last Sunday’s attacks, including a number of Somalis.

Somalia’s al Shabaab rebel group has told Reuters it was not behind the church strikes.

A senior regional police commander, Philip Ndolo, said no-one had been charged yet in connection with the attacks.

At a packed service at the AIC church on Sunday, dried blood still stained the floor, bullet holes pocked the walls and beams of light poured through the metal-sheet roof punctured last week by flying shrapnel.

“The guys who attacked us are not (true) Muslims because their faith does not allow this,” said Daniel Mwinzi, who still carries head wounds and was partially deafened by the blasts.

In a show of unity, Muslim leaders in Garissa visited the town’s churches.

“We were saddened by what happened and (our presence) is in solidarity with our Christian brothers,” said Abdullahi Salat, chairman of the Supreme Council of Kenyan Muslims in Garissa.

Earlier in the week, Christian and Muslim leaders pledged to protect each others’ faithful.

“War against Christians is a war against Muslims too, because we are all Kenyans,” Sheikh Khalifa Mohammad of the Council of Imams and Preachers told Reuters.