ISIS claimed responsibility for Monday’s deadly, hours-long rampage at Afghanistan’s Kabul University — as the official death toll rose to 22 and maybe more, according to reports.

The terror group’s propaganda arm said it was behind the attack, which was carried out by two gunmen who stormed the campus after a suicide bomber struck around 11 a.m. local time, AFP said.

At least 22 people were reported killed and 22 more were injured, according to The Associated Press.

Many of the wounded were in critical condition, leading to fears that the death toll would increase further, AP said.

Most of the casualties were students, some of whom were left laying in pools of blood in their classrooms, with grisly images of the carnage posted online.

Hundreds of others fled in terror as the horror unfolded, scrambling to safety over the protective walls and fences surrounding the 17,000-student school.

Survivor Fraidoon Ahmadi, 23, said he was in class when the gunfire erupted and spent two hours huddled with terrified fellow students before being rescued.

“We were very scared and we thought it could be the last day of our lives…boys and girls were shouting, praying and crying for help,” Ahmadi told AFP.

All three attackers were killed, according to an Interior Ministry spokesman.

An investigation was underway to determine how the radical Islamic terrorists got their weapons past the school’s security checkpoints.

The incident coincided with a book fair attended by the Iranian ambassador and touched off a gun battle with Afghan special forces and US troops that lasted about five hours.

ISIS said it targeted newly graduated “judges and investigators belonging to the apostate Afghan government” gathered at the campus, AP said, citing the SITE Intelligence Group, which monitors terror online messaging.

ISIS didn’t say whether it had planned to attack the Iranian envoy or the book fair, and claimed only two of its fighters were involved, AP said.

The attack followed another by ISIS on a tutoring center in Kabul that killed at least 24 students and wounded more than 100 others on Oct. 24.

That assault took place in Dasht-e-Barchi, a mostly Shiite neighborhood in the Afghan capital.

The terror group has declared war on Afghanistan’s Shiite minority and was blamed for a barbaric attack on a maternity hospital in Dasht-e-Barchi that killed 25 people.

Many of those victims were newborn babies and mothers.