Taliban gunmen stormed a military school in Pakistan on Tuesday, killing dozens of students and wounding many more, Pakistan’s military said.

It was not immediately clear if hostages were being held.

The attack began in the early morning, with the gunmen entering the school — a military-run facility in the northwestern city of Peshawar with students in grades 1-10 — and shooting at random, said police officer Javed Khan. Army commandos quickly arrived at the scene and exchanged fire with the gunmen, he said.

Pervez Khattak, the chief minister of the province, said as many as 84 children were killed, but there were unconfirmed reports the figure may be far higher.

According to Khattak, the 84 killed in the Tuesday attack were all “children” but hospital officials earlier said at least one of the fatalities was a teacher and one security official were also among the dead.

Jamil Shah, a spokesman for Lady Reading Hospital in the city, said the killed security official was a member of the Pakistani paramilitary forces.

Student Abdullah Jamal, who was shot in the leg, said he was with a group of 8th, 9th and 10th graders who were getting first-aid instructions and training with Pakistani army medics when the attack began. For the first few seconds, nobody knew what was happening, he said.

“Then I saw children falling down who were crying and screaming. I also fell down. I learned later that I have got a bullet,” he said from his hospital bed.

“All the children had bullet wounds. All the children were bleeding.”

Taliban spokesman Mohammed Khurasani claimed responsibility for the attack in a phone call to media, saying that six suicide bombers carried out the attack in revenge for the killings of Taliban members at the hands of Pakistani authorities.

Prime Minister Nawaz Sharif condemned the attack and said “those behind the heinous act will not be spared,” The Express Tribune newspaper in Pakistan reported.

Peshawar has been the target of frequent militant attacks, but Tuesday’s incident was the highest-profile militant attack to hit the troubled region in months.

Contributing: Associated Press