At least four people died and some 30 others were wounded when an assailant hurled grenades inside a movie theater in the northwestern city of Peshawar, a Pakistani police officer told Efe on Monday.

Around 100 people were inside the cinema at the time of Sunday night's attack, Harun Khan said.

Many of the injured were hurt in the stampede that followed the explosions, according to witnesses cited by local media.

"It took almost 20 minutes to evacuate the theater," one of the guards told the daily Express Tribune, adding that upon returning to the interior of the theater he found "eight people who had been in the rows of seats, some dead and others wounded."

No group has claimed responsibility for the attack, and the Pakistani Taliban, known as the TTP, have denied staging it, but in the past groups linked to armed fundamentalists have carried out attacks against movie theaters in Peshawar and other cities.

Theaters, in fact, are a relatively common target of radical Islamist groups.

In 2009, six people died in an explosion at the entrance of a theater in Peshawar located very near the one attacked Sunday night.

The city is the capital of the violence-plagued province of Khyber Pakhtunkhwa, which borders on Afghanistan and is a refuge for Taliban cells, jihadist groups and criminal organizations that operate on both sides of the porous frontier.

According to a recent report by the Pakistan Institute for Peace Studies, last year there were more than 1,700 terrorist attacks in the country, 61 percent of them perpetrated by the TTP and its allies. EFE