Christians in eastern Kenya are on high alert after a wave of attacks by Somali Muslims.

One pastor in the Garissa area who cannot be named for security reasons told Open Doors that Christians are scared of attacks and as a result, are staying away from church.

Open Doors said the town of Garissa, which is around 50 miles away from the border with Somalia, has been the scene of several attacks and "has been nearly overrun by Somali Muslims".

A recent hand grenade attack on a kiosk in Bula Punda, which injured eight people, has left locals feeling nervous about their security.

Four of the injured have since been released from hospital. The other four are still being treated for shrapnel wounds.

One suspect has been arrested by authorities in connection with the attack.

Many of those living in Garissa are referred to as "down-Kenyans" because they have come to the city from other parts of the country to work.

The pastor who spoke to Open Doors believes it is these down-Kenyans who are being targeted in the attacks because they are regarded as outsiders and an "unwelcome Christian presence in the Muslim-dominated area".

Another pastor who cannot be named for security reasons was distressed in a phone call to Open Doors.

"As Christians, we are asking, when will this end? Will it ever end?" the pastor said.

"Our Christian fellowship, spiritual growth and even our economy are being affected. Please pray for security, strength for the church and that God will watch over His people."

The recent series of attacks has led to Kenya being ranked once again on Open Doors' World Watch List of 50 countries where Christians experience the greatest persecution.

Kenya was ranked 43 after an absence from the list for many years.

It is not only in Garissa that being a Christian has become harder. Open Doors says that across Kenya, churches are experiencing greater levels of persecution and that the government's attitude to religious institutions is hardening.

Last year's deadly attack on a shopping mall in Nairobi by al-Shabaab has also exposed the threat of radical Muslims.

Open Doors said the challenge for the church was to "engage constructively" with the pressures it is facing.