PESHAWAR, Pakistan - Taliban gunmen stormed an army-run school in Pakistan on Tuesday, killing at least 95 people including 82 children in one of the country's bloodiest attacks in recent years, officials said.
Witnesses described how a huge blast shook the Army Public School in the northwestern city of Peshawar and gunmen went from classroom to classroom, shooting children.
The Tehreek-e-Taliban Pakistan (TTP) claimed responsibility for the attack as retaliation for a major military offensive in the region, saying militants had been ordered to shoot older students.
The attack began around 10.30 am (0530 GMT) when a group of at least five insurgents, reportedly in military uniforms, entered the school.
Pakistan's military headquarters said a "rescue operation" was under way, with troops still exchanging fire with attackers more than three hours after the incident began.
A security official told AFP that hundreds of students and staff were in the school when the attack began, though according to the military the bulk of them have been evacuated.
It is not clear how many are still in the school.
Peshawar's Lady Reading Hospital received 26 bodies, spokesman Jamil Shah said, while a report from the city's Combined Military Hospital seen by AFP said they had 69 dead.
Provincial information minister Mushtaq Ghani said many of the dead were killed in a suicide blast.
Mudassar Abbas, a physics laboratory assistant at the school, said some students were celebrating at a party when the attack began.
"I saw six or seven people walking class-to-class and opening fire on children," he said.
A student who survived the attack said soldiers came to rescue students during a lull in the firing.
"When we were coming out of the class we saw dead bodies of our friends lying in the corridors. They were bleeding. Some were shot three times, some four times," the student said.
"The men entered the rooms one by one and started indiscriminate firing at the staff and students."
The school on Peshawar's Warsak Road is part of the Army Public Schools and Colleges System, which runs 146 schools nationwide for the children of military personnel and civilians. Its students range in age from around 10 to 18.
The schools educate the children of both officers and non-commissioned soldiers and army wives often teach in them.
TTP spokesman Muhammad Khorasani told AFP there were six attackers.
"They include target killers and suicide attackers. They have been ordered to shoot the older students but not the children," he said.
"This attack is a response to Zarb-e-Azab and the killing of Taliban fighters and harassing their families." Zarb-e-Azb is the official name for the army's offensive against strongholds of the Taliban and other militants in North Waziristan.
The military has hailed the operation as a major success in disrupting the TTP's insurgency, which has killed thousands of Pakistanis since it erupted in 2007.
More than 1,600 militants have been killed since the launch of Zarb-e-Azb in June, according to data compiled by AFP from regular military statements.
Talat Masood, a retired general and security analyst, said the attack was intended to weaken the military's resolve.
"It is both tactical and strategic. The militants know they won't be able to strike at the heart of the military, they don't have the capacity because the army are prepared," Masood told AFP.
"So they are going for soft targets. These attacks have a great psychological impact." The semi-autonomous tribal areas that border Afghanistan have for years been a hideout for Islamist militants of all stripes - including Al-Qaeda and the homegrown TTP as well as foreign fighters such as Uzbeks and Uighurs.
Washington pressed Islamabad for years to wipe out the sanctuaries in North Waziristan, which militants have used to launch attacks on NATO forces in Afghanistan.