A Kenya Defence Force soldier runs for cover near the perimeter wall of Garissa University College. Credit:Reuters Somalia's al-Shabab Islamist group claimed responsibility for the attack, saying it had released Muslims while killing some Christians and taking many others hostage inside. "We sorted people out and released the Muslims," Sheikh Abdiasis Abu Musab, al-Shabab's military operations spokesman, said. "There are many dead bodies of Christians inside the building. We are also holding many Christians alive. Fighting still goes on inside the college." President Uhuru Kenyatta ordered the police to speed up the recruitment of police officers to help battle the Somali-based militants after the attack Thursday. Al-Shabaab has escalated the number and deadliness of attacks since 2011 when Kenya sent troops to fight them in Somalia. The group killed 67 people in a multi-day siege of a popular mall in Nairobi, the capital, in 2013.

Kenyan police officers take cover outside the Garissa University College during the attack. It's unknown how many students have been taken hostage. Credit:AP "My government has undertaken appropriate deployment to the affected area and is fully in charge of the situation," Kenyatta said. "This is a moment for everyone throughout the country to be vigilant as we continue to confront and defeat our enemies." The militants may have chosen the university as a "soft target, an area with a big population," Emmanuel Kisiangani, a Nairobi-based senior researcher at the Institute for Security Studies, said by phone. Kenya Defence Force soldiers patrol the perimeter wall where the Islamists are holding hostages and executing Christians at a campus in Garissa. Credit:Reuters "Al-Shabaab usually come up with attacks when they are perceived to be at their weakest point. I think they did this as part of the agenda to assert themselves," he said.

The death toll in a university attack in northeastern Kenya rose to at least 147 on Thursday, with another 79 wounded, but the siege was almost over, Kenya's Interior Minister Joseph Nkaissery said. Students of the Garissa University College get out of a house where they were taking shelter from an attack by Islamist gunmen in Garissa, Kenya. Credit:AP Nkaissery cautioned that "the operation is ongoing, anything can happen." At the same press conference in Garissa, Kenyan Police Chief Joseph Boinet said the east African country has introduced a dusk to dawn (6.30pm - 6.30am) curfew for four regions near Somalia border as a security precaution. Heavy gunfire and explosions were heard and siege was coming to an end as Kenyan forces moved into the Garissa University College. Credit:Google Maps

Some students were trapped inside the college campus, the Centre said. The wounded were all taken to hospital, with four in a critical condition. Most had gunshot wounds. "We have 49 casualties so far, all with bullet and (shrapnel) wounds," said a doctor at Garissa hospital. A Kenya Defense Force soldier stops a boy from moving in the direction where Islamists are holding hostages on a campus in Garissa. Credit:Reuters Kenyan troops have killed two gunmen from a gang of Somalian Al-Shabab Islamist fighters who stormed a university. "Two of the terrorists have been killed and the security forces are doing their best to free the hostages," Interior Ministry spokesman Mwenda Njoka said earlier, with "security agencies intensifying the rescue operation".

Medics help an injured person at Kenyatta national Hospital in Nairobi, Kenya, after being airlifted from Garissa. Credit:AP Heavy gunfire and shouts from inside the building where hostages were believed to be held were heard by journalists with the Kenyan troops, as soldiers continued to battle the insurgents as darkness fell, over 12 hours after the attack began. Soldiers told a journalist at the scene that they had heard screaming from inside the building, including shouts of "Allah hu Akbar", or "God is the greatest" in Arabic. Students gather and watch from a distance outside the Garissa University College after an attack by Islamist gunmen. Credit:AP One suspected gunman was earlier arrested as he tried to flee the campus.

Police and soldiers surrounded and sealed off the university and were attempting to flush out the gunmen, Police Chief Boinet said in a statement. Local residents donate blood at Garissa hospital after the attack. Credit:AP "The attackers shot indiscriminately while inside the university compound," Mr Boinet said, adding that police had been guarding the university's four hostels at the time. One student who fled, Njeri Maina, said three assailants entered the university's main accommodation building carrying assault rifles and grenades. A Kenya Defence Forces tank arrives at Garissa University College. Credit:AP

They shouted in Arabic, then Swahili, telling everybody to lie down before they opened fire, she said by phone. "I managed to lock myself in a nearby toilet and leave the building through the back entrance after security forces started engaging the attackers," Maina said. A policewoman at the scene said two security guards at the campus had been killed and many students remained trapped inside the campus in Garissa, nearly 400 kilometres east of Nairobi. "Two guards who were manning the gate at the university have been killed," she said. "We can hear gunshots from inside the compound but at this point we can't tell who is shooting at who or what." A Kenyan blogger and student, Robert Alai, based in Nairobi, told Fairfax Media he had spoken by phone to three teacher friends who were hiding on the campus. "The attackers were shooting at anyone in sight, inside the college," he said.

Mr Alai said the attackers may also have used grenades. "Most of the people I've spoken to are scared," he said. "We heard some gunshots and we were sleeping so it was around five and guys started jumping up and down running for their lives," an unnamed student said. Witnesses recount horror of attack An explosion followed by gunfire woke students at Garissa's Moi University in Kenya before dawn on Thursday morning. At around 5:30 am an unknown number of masked gunmen began an assault by tossing explosives at the main gate before storming a nearby girl's hostel.

More than 800 students attend the university and sleep in dormitories on the sprawling campus on the outskirts of the town in northeast Kenya. "We were sleeping when we heard a loud explosion that was followed by gunshots and everyone started running for safety," said student Japhet Mwala. "There are those who were not able to leave the hostels where the gunmen headed and started firing, I am lucky to be alive because I jumped through the fence with other students," said Mwala. Another student, Katherine - who did not want to give her full name - said that when she first heard the explosion and gunfire, "we thought that it was power problems". But soon the horror of being caught up in the latest attack by the Al-Qaeda aligned militants from neighbouring Somalia dawned on her.

'We thought warning was April Fool' "We started running away," she said. Katherine and other students fled their hostels and ran to nearby fields where they hid as the gunfire continued. Rosalind Mugambi also fled to the fields with other students and "bullets following us". She said some of her friends were injured by the gunfire. "We saw some blood stains and they were shot," she said. Students said that notices had been posted around the campus warning that an attack was possible.

"There were reports of an attack the whole week and even the university administration was informed," said Nicholas Mutuku. "But it is like everyone didn't take it seriously, because it was not the first time such reports were emerging." Some who saw the warning notices a day ahead of the attack thought they were an April Fool's prank. "Yesterday there were those notices, but as it was April 1, we just thought that it was fooling," said Katherine. Christians separated from Muslims

Al-Shabaab, which seeks to impose its own harsh variant of sharia law, had separated Muslims from Christians in some of its previous raids in Kenya, notably late last year in attacks on a bus and at a quarry. Its repeated raids, together with attacks on churches by home-grown Islamist groups, have in recent years strained the historically cordial relations between Kenya's Muslim and Christian communities. Thursday's attack also marked a setback in a drive by President Uhuru Kenyatta to persuade foreigners the country is safe to visit. On Wednesday, he urged Kenyans abroad to help woo tourists back despite the wave of militant violence, criticising a warning from Australia of a possible attack in Nairobi and an advisory from Britain urging its citizens to avoid most coastal resorts. Kenyatta was due to address the nation about the Garissa attack later on Thursday.

Grace Kai, a student at the Garissa Teachers Training College near the university, said there had been warnings that an attack in the town could be imminent. "Some strangers had been spotted in Garissa town and were suspected to be terrorists," she said. "Then on Monday our college principal told us ... that strangers had been spotted in our college ... On Tuesday we were released to go home, and our college closed, but the campus remained in session, and now they have been attacked." Al-Shabaab had previously carried out attacks in Garissa, which lies around 200 kilometres from the porous Somali border. Many Kenyans living in the crime-ridden frontier regions blame the government for not doing enough to protect its citizens from the militants.

Having declared it would punish Kenya for sending troops into Somalia to fight it alongside African Union peacekeepers, it was also responsible for a deadly attack in 2013 on the upscale Westgate shopping mall in Nairobi. Reuters, AP, AFP First published on April 2, constantly updated.