At least 20 people are dead and 50 injured after a group of militants stormed a university in northwestern Pakistan on Wednesday, in an attack that lasted hours.
The gunmen used the cover of thick, wintry fog to scale the walls of the Bacha Khan University in Charsadda, northwestern Khyber Pakhtunkhwa province, before entering buildings and opening fire on students and teachers.
A senior security officer at the scene told Reuters on Wednesday that 90 percent of the campus had been secured after a three-hour gunfight with the militants ended. A Charsadda District local government official told VICE News that the operation had come to an end. "The army is busy clearing the university block to block, it may take some time," he said.
Four militants had been killed, the army said. Security sources told VICE News that the four attackers were wearing suicide vests, but were killed by security forces before they could detonate their explosives.
Local newspaper Dawn reported that students inside the university's grounds had been gathering for a poetry recital to commemorate the anniversary of the death of Khan Abdul Ghaffar Khan, a popular ethnic Pashtun independence activist and leader after whom the university is named.
Regional politician Shaukat Yousufzai told VICE News that number of dead was between 25 and 30. Fakhr-i-Alam, a senior government official, said at least 19 had been killed, while an official Twitter handle for the Government of Khyber Pakhtunkhwa said there had been "around" 25 deaths and 30 injuries, before declaring three days of mourning.
A security official said the death toll could rise to as high as 40 as the army cleared out student hostels and classrooms. A spokesman for the rescue workers said the dead included students, guards, policemen and at least one professor, while a post on the University's Facebook page said a chemistry professor, two guards, two women, and two policemen were among those killed.
Around 3.30pm local time an army official told Associated Press the operation was over and 20 people were dead.
The Pakistani Taliban initially claimed responsibility for the attack in an email issued to local media. Umar Mansoor, a commander in the Tehreek-e-Taliban Pakistani (TTP) militant group told AFP: "Our four suicide attackers carried out the attack on Bacha Khan University today." He said it was a response to a military offensive against extremists in the tribal areas.
But a Facebook post by Mansoor claiming responsibility was later removed, and another TTP spokesman said the organisation was not responsible and condemned it, according to the Express Tribune.
Vice Chancellor Fazal Rahim told reporters that the university teaches over 3,000 students and was hosting an additional 600 visitors on Wednesday for the recital.
Television footage showed soldiers entering the campus as ambulances lined up outside the main gate and anxious parents consoled each other.
Shabir Khan, a lecturer in the English department, said he was about to leave his university housing for the department when firing began.
"Most of the students and staff were in classes when the firing began," Khan said. "I have no idea about what's going on but I heard one security official talking on the phone to someone and [he] said many people had been killed and injured."
One mother of a missing student told reporters: "My daughter called me when the attack started and I rushed to the university — now her mobile is switched off. I have searched in every hospital and not found her."
Another student, Aizaz Khan, told Reuters: "We heard firing from the back of the campus. We thought maybe some people were fighting. Then the firing increased. Then we said: 'Get into the rooms. Don't go out'. Then the security forces came. They showed great bravery. The Pakistani army also showed great bravery."
Student Zahoor Ahmed told the media outside he had tried to run once he heard firing, but his chemistry teacher Syed Hamid advised him to stay inside. Hamid was holding a pistol which he used to hold off the attackers until he was shot himself.
Ahmed then escaped by jumping from the roof of the building he was in.
Another student Mumtaz Khan praised Hamid, saying: "If teacher Dr Syed Hamid not stopped the terrorist and if they succeeded to enter… then the terrorists would have killed all the students, but Dr. Syed Hamid gave his life and saved us all."
Pakistani Prime Minister Nawaz Sharif released a statement after Wednesday's attack, saying he was "deeply grieved."
"We are determined and resolved in our commitment to wipe out the menace of terrorism from our homeland. The countless sacrifices made by our countrymen will not go in vain Inshallah."
Indian Prime Minister Narendra Modi tweeted his condolences to the families of the deceased.
The US embassy in Pakistan also tweeted to condemn the attack, saying: "Our thoughts are with the victims and their families."
Pakistan's media regulator Pakistan Electronic Media Regulatory Authority (PEMRA) has also directed the media not to reveal the movements of security personnel or students during their coverage of the attack, according to Radio Pakistan.
Pakistan, which has suffered from years of jihadist militant violence, has killed and arrested hundreds of suspected militants under a major crackdown launched after the massacre of 132 school children in December 2014 in Peshawar.
The Peshawar attack — carried out by six Pakistani Taliban gunmen just 25 miles from the Bacha Khan University— hit a raw nerve in Pakistan and was seen as having hardened Pakistan's resolve to fight militants along its lawless border with Afghanistan.
Watch the VICE News documentary: Life After the Massacre: Terror in Peshawar:
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Reuters contributed to this report.
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