Sawt Falasteen - Thousands gather as Pakistan buries victims of mosque suicide attack

Friday's attack, which was claimed by the Islamic State group, was the deadliest in Islamabad since the 2008 Marriott hotel bombing.

City officials said 31 people were killed and another 169 were wounded in the explosion at the Imam Bargah Qasr-e-Khadijatul Kubra mosque on the city's outskirts. The death toll was expected to rise.

Tearful mourners gathered at locations across Islamabad to bury the dead.

"What happened yesterday has left us extremely angry and deeply hurt," Bushra Rahmani, whose brother was among the wounded, said at one funeral.

Syed Jamil Hussain Shah, a 45-year-old resident of the capital, said: "Whatever happened was completely wrong and against humanity."

Officials including a senior police officer in Pakistan's northwest said on Saturday that some of the bomber's relatives had been arrested.

The officer, who did not give his name, said the attacker was from Peshawar, the capital of the violence-racked western province of Khyber Pakhtunkhwa, and that some of his relatives had been living in Nowshera on the road to the capital for several years.

A security official told AFP on the condition of anonymity that the attacker's mother was taken into custody in an upmarket neighbourhood of Islamabad, and that his brother and others were also arrested in different parts of the country.

Officials did not specify on what charges they had been arrested or how many people had been taken into custody.

- Bodies, bloodied clothing -

The blast occurred during Friday prayers, when mosques are packed with worshippers. A security source told AFP that the attacker blew himself up after he was stopped at the mosque's gate.

A worshipper, Imran Mahmood, told AFP that there was a gunfight between the bomber and volunteer security personnel.

"He then detonated the explosives", Mahmood said.

Prime Minister Shehbaz Sharif condemned the blast and vowed that those responsible would be found and brought to justice.

Deputy Prime Minister Ishaq Dar branded it "a heinous crime against humanity and a blatant violation of Islamic principles".

AFP journalists at a major hospital on Friday afternoon saw several people, including children, being carried in on stretchers or by their arms and legs.

Medics and bystanders helped unload victims with blood-soaked clothes from the back of ambulances and vehicles as friends and relatives of the wounded wept and screamed.

Heavily armed security forces guarded the mosque, where pools of blood were visible on the ground.

Videos shared on social media, which AFP was not able to verify immediately, showed several bodies lying near the mosque's front gate, with people and debris also strewn across the red-carpeted prayer hall.

- Growing insurgencies -

The attack comes as Pakistan's security forces battle intensifying insurgencies in southern and northern provinces that border Afghanistan.

Pakistan is a Sunni-majority nation, but Shiites make up between 10 and 15 percent of the population and have been targeted in attacks throughout the region in the past.

In Balochistan in the southwest, attacks claimed by separatist insurgents last week killed 36 civilians and 22 security personnel, prompting a wave of counter-operations in which authorities said almost 200 militants were killed.

Friday's attack was the deadliest in Islamabad since September 2008, when 60 people were killed in a suicide truck bomb blast that destroyed part of the five-star Marriott hotel.

Z.Ramadan--SF-PST