A group of terrorists stormed into a major hospital in Lahore early Tuesday, killing at least four people before fleeing, according to the police.

Among the patients at Jinnah Hospital were 35 victims from the brazen attacks on Friday at two mosques in Lahore that killed more than 80 members of a minority Muslim sect called the Ahmadis.

Another patient at the hospital was a terrorist who was injured in Friday’s attack.

It was not known if Tuesday’s assault was an attempt to kill the 35 injured Ahmadis or a bid to rescue the injured terrorist.

The hospital’s chief executive, Dr. Javed Ikram, , said the attackers entered the emergency ward by firing indiscriminately, killing guards, policemen and possibly some visitors. Dr. Ikram’s voice was trembling as he spoke to local television stations on Tuesday morning.

The provincial Punjab police force called in large numbers of armored vans and elite forces as the firing continued, but the terrorists manged to escape. Local television reports said there appeared to be from four to six terrorists.

The Pakistani Taliban have claimed responsibility for Friday’s attacks. The Taliban, who are Sunni Muslim, have increasingly focused on attacking minority Muslim groups.

There are about 2 million Ahmadis Pakistan, where the sect has suffered severe discrimination in Pakistan for decades. Ahmadis are considered heretical by many mainstream Muslims because they believe that Mirza Ghulam Ahmad, who founded their movement in 1889, was the messiah foretold by Muhammad, the prophet of Islam.