A worshipper at the Shiite mosque in Islamabad, Pakistan's capital city, where dozens of people were killed in a suicide blast on Friday has described an "extremely powerful" explosion ripping through the building just after prayers started.
Muhammad Kazim, 52, said he arrived at the Imam Bargah Qasr-e-Khadijatul Kubra mosque shortly after 1pm local time (7pm AEDT) on Friday and took up a place around seven or eight rows from the imam.
"During the first bow of the Namaz (prayer ritual), we heard gunfire," he told AFP outside the Pakistan Institute of Medical Sciences (PIMS) hospital, where many of the wounded were brought for treatment.
"And while we were still in the bowing position, an explosion occurred," he said.
Kazim, who is from Gilgit-Baltistan in northern Pakistan and lives in Islamabad, escaped unharmed, but he accompanied his wounded friend to the PIMS hospital for treatment.
"It was unclear whether it was a suicide bombing, but the explosion was extremely powerful and caused numerous casualties," Kazim said.
"Debris fell from the roof, and windows were shattered," he added. "When I got outside, many bodies were scattered ... Many people lost their lives."
The so-called Islamic State (IS) group has claimed responsibility for the attack, according to the SITE Intelligence Group, which monitors jihadist communications.
Dozens killed, over 150 injured
Another worshipper, Imran Mahmood, described a gunfight between the suicide bomber, a possible accomplice and volunteer security personnel at the mosque.
"The suicide attacker was trying to move forward, but one of our injured volunteers fired at him from behind, hitting him in the thigh," Mahmood, in his fifties, told AFP.
"He fell but got up again. Another man accompanying him opened fire on our volunteers," he said, adding the attacker "then jumped onto the gate and detonated the explosives".
As of Saturday morning, the death toll stood at 31, with at least 169 wounded.
The attack was the deadliest in the Pakistani capital since September 2008, when 60 people were killed in a suicide truck bomb blast that destroyed part of the five-star Marriott hotel.
'Never seen proper security'
Describing the aftermath of the attack, Kazim said unhurt worshippers went to the aid of those wounded.
"People tried to help on their own, carrying two or three bodies in the trunks of their vehicles, while ambulances arrived about 20 to 25 minutes later," he told AFP.
"No-one was allowed near the mosque afterwards."
Kazim, who has performed Friday prayers at the mosque "for the past three to four weeks", said security had been lax.
"I have never seen proper security in place," he told AFP.
"Volunteers manage security on their own, but they lack the necessary equipment to do it effectively," he said.
"Shiite mosques are always under threat, and the government should take this seriously and provide adequate security," he added.
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