A gun and bomb attack on a university in north-west Pakistan, where 21 people were killed and 17 people were left injured, was ended by security forces on Tuesday.
The battle lasted nearly three hours at Bacha Khan University in Charsadda. Grenades and automatic weapons were used. Four suspected attackers also died in the gunfire.
One Pakistani Taliban commander said the group had carried out the assault, but its main spokesman denied this.
In 2014, the militant group killed 130 students at a school in the city of Peshawar, 30 miles from Charsadda.
At 9.30am in the morning on Wednesday, the attackers struck under the cover of thick winter fog. They climbed over a back wall and began their onslaught.
Intense gunfire and explosions were heard as security guards fought the attackers.
Khyam Mashal, a student at the university, was in the boys' hostel on the campus, where he lives, when the militants attacked.
He told CNN news that he was sleeping when a friend woke him to tell him that terrorists were attacking the school.
He says he was ‘shocked’ that the attackers had breached the school's security.
He said: “I looked through the window... there were two, three people firing, and I think they were the terrorists. I'm so afraid... my country is not safe. I'm not feeling comfortable.”
Pakistan observed a day of national mourning on Thursday for those killed in the attack.
All government buildings inside and outside the country flew their flags at half-mast, while prayer ceremonies were also held in the capital, Islamabad.
Prime Minister of Pakistan, Nawaz Sharif has vowed a ‘ruthless’ response to the massacre and ordered security forces to hunt down those behind Wednesday’s attack.
He said in a statement: “We are determined and resolved in our commitment to wipe out the menace of terrorism from our homeland.”