The chair of the Garissa Christian Students' Union in Kenya has told Open Doors workers about his harrowing experience during the Moi University attack this Maundy Thursday, 2 April, which killed at least 148 of his fellow students and injured 79.

Frederick Gitonga, 21, believes God prevented more people from dying, as the usual 60-70-large prayer gathering was only attended by 22 people that day, all of whom were tragically killed when terrorists from al-Shabaab, the Somali-based Islamist terror group, opened fire on their campus. The attack had begun at 5.30am, with explosives thrown at the university's main gate and gunmen firing indiscriminately.

He himself avoided danger due to oversleeping after a late-night prayer session, and after hearing gunshots and screams he hid under his bed rather than following others out into the open. Two attackers entered his room and tested their rifles against the wall, but Frederick remained hidden and was later rescued by a Kenyan Defence Force officer.

Witnesses have spoken of how the gunmen headed directly to the lecture hall where students had gathered for early-morning prayer, and how hostages were separated according to their faith, with Christians targeted in execution-style killings. News agency Reuters quoted a spokesman for the terrorist group saying: "There are many dead bodies of Christians inside the building. We are also holding many Christians alive."

Al-Shabaab has conducted similar attacks in Kenya where Christians have been murderously-targeted and separated due to their religion, CSW reports. These include the attack on a Mandera quarry in December 2014, the hijacking of a bus to Nairobi in November 2014 and the Westgate shopping mall siege of September 2013 which left five security officers and 62 civilians from 13 countries dead.

Experts are questioning whether the Kenyan government has learnt anything about dealing with terrorist attacks from these atrocities, as posters warning of the university siege were reportedly displayed on the Garissa campus before 2 April, and university administrators are said to have been warned about an imminent attack. But it seems these warnings were "ignored" or dismissed as April Fool's pranks. A neighbouring college had also been warned about suspected terrorists walking around the city and decided to close to protect students.

The leaders of mainstream Christian churches in Kenya have said in a joint statement: "The systematic profiling, isolation and massacre of Christians in different parts of Kenya must stop.… While urging our Christians to be peace makers, we will not remain silent as they continue being massacred.… We shall not tire in reminding the government to take its responsibility to protect every Kenyan more seriously."

Al-Shabaab have increased attacks in Kenya since October 2011 when Kenya's army joined efforts to stabilise Somalia following the abductions of foreign tourist groups across the border. The terror group formally aligned itself with al Qaeda in 2012, and increasing numbers of Kenyan young men are reported to have been recruited, with 26 young men from one town suspected to have recently joined the Islamist group.

Somalia, which neighbours Kenya to the east, is ranked second in Open Doors' World Watch List, meaning it is one of the most difficult places in the world to live as a Christian. Islam is declared the state religion by Somalia's constitution, stating that that "no law can be enacted that is not compliant with the general principles and objectives of Shari'a". There is also deep hostility to conversion, with converts considered apostates and often executed on the spot. This means it is too dangerous for Christians in Somalia to worship together or even own a Bible.

Al-Shaaab has publicly declared that it "wants Somalia free of any Christians", regularly executing them and also targeting Christians in Kenya and Tanzania. The Islamist group holds sway over most of southern and central Somalia, including key ports, giving them easy access to neighbouring nations. Just days ago they killed six people, including four aid workers for UNICEF, in a bomb near the north-eastern Somali city of Garowe.

Ciku Muriuki, a popular radio presenter in Kenya, wrote an open letter to the Garissa attackers on Facebook, comparing the deaths of the innocent students to Jesus' death and victory at Easter. She ends with these words of forgiveness:

"…So, to all you al-Shabaab guys who have killed my Christian brothers and sisters, I forgive you. Yes, you heard me right. I forgive you. As you fill your heart with hate (just as those angry mobs did 2,000 years ago), I will fill my heart with love – like Jesus did – for truly, you know not what you do."

Frederick is calling on the worldwide Church to pray for the students of Garissa, for healing in mind as well as body following the atrocities they have witnessed. They also need God's wisdom as they relocate to the main university campus Eldoret on 20 May.

"I praise God that some survived, many in truly miraculous ways." Frederick says. "However, we are deeply traumatised, broken, and in need of much prayer. At the same time, we are trying to help fellow students who seek comfort and support from us."

Please pray:

• for God's grace and healing for the victims of the Garissa attack and their friends and families;
• that God will raise up leaders of integrity who will lead Kenya effectively and bring peace and reconciliation;
• for strength, protection and effective support for Christians in Kenya and Somalia, particularly Muslim-converts who are at risk of violent attack if their new faith is discovered;
• for stability in Somalia, and that a strong government will be formed that will prioritise religious freedom and root out extremism.

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