Pakistan's Army Chief of Staff Gen. Raheel Sharif has arrived at the Bacha Khan University in Khyber Pakhtunkha's Charsadda town to oversee the clearance operation by military forces following Wednesday's deadly attack against the facility.

Officials have so far confirmed that four gunmen have been killed but that troops continue their clearance operation in the building.

KPK provincial minister Shaukat Yousafzai told TOLOnews reporter Abdulhaq Omeri that the death toll has risen to 25 with over 50 people wounded.

However, other officials said the death toll could rise to over 30, especially as a number of wounded are in critical condition.

The incident took place early Wednesday when gunmen stormed the university and opened fire on students and faculty members that had gathered for a poetry recital to commemorate the death anniversary of the activist and leader whom the school is named after.

During the siege, local media reported that concerned families and friends of students and faculty staff had gathered in large numbers outside the cordoned off university as they anxiously awaited updates.

Dawn news reported that about 20 ambulances had entered the university and transferred most of the wounded to the District Headquarter Hospital. However, a number of patients are in critical condition and are expected to be transferred to Peshawar.

Among the dead is the chemistry department's professor Hamid Hussain.

Wednesday's siege was reminiscent of the deadly December 2014 terrorist attack on the Army Public School in Peshawar which left over 140 dead — most of them students.

A student speaking to DawnNews said the attackers appeared to be young.

He said that in the hostel alone there had been between 200 and 300 students, who had taken cover until military forces cleared their building.

The attackers were like us ─ they were very young. They carried AK-47 guns. They wore jackets like the forces do... We were in the hostel sleeping as we don't have classes.

There are no classes at the university currently, there may be around 200-300 students in the hostel.

There was firing between attackers and security forces. After everything was over, the army men knocked on our room and told us we were safe.