At least 30 people were killed after an explosion ripped through a Shiite place of worship in Terlai on the outskirts of the Pakistani capital.

A blast hit a Shiite Muslim mosque in Pakistan's capital, Islamabad, during Friday prayers, police said.

Pakistani daily Dawn reported that explosion occurred at the Imambargah Khadijah al-Kubra in the Terlai area on the outskirts of the capital.

The newspaper said that 31 people had been killed in the explosion and 169 had been injured. Hospitals in the city were put on high alert.

In a separate report, Dawn cited Islamabad police spokesperson Taqi Jawad as saying that it could not initially be established whether the incident was a suicide bombing or the result of a planted bomb.

AFP news agency cited an unnamed security source as saying that a suicide bomber was behind the attack.

Prime Minister Shehbaz Sharif expressed his "deep grief" over the incident in a statement, saying that he "strongly condemns" the blast.

President Asif Ali Zardari issued his condolences to the victims' loved ones in a post on X.

"Targeting innocent civilians is a crime against humanity," he said, according to the post issued by his PPP party.

Attacks on Shiites in Pakistan

A majority of Pakistanis are Sunni Muslims, while some 15% belong to the Shiite minority.

Islamist groups such as the Pakistani Taliban (TTP) and the "Islamic State" group have carried out attacks on Shiites in the past, with many Sunni extremists considering them to be apostates.

No specific group immediately claimed responsibility for the Friday explosion.

Pakistan has been grappling with a major security crisis for years, battling armed Islamist groups as well as Baloch separatists in the country's southwest.

The Friday explosion comes after a dozen people were killed in a suicide attack outside an Islamabad district court in November.