RIYADH: A suicide bomber detonated an explosives vest during Friday weekly prayers at a Shia mosque in eastern Saudi Arabia, killing 21 people and wounding several others, a hospital official said.

The official reached by telephone said more than 90 other people were wounded, including some who are in serious condition.

The kingdom's Eastern Province has been hit by previous attempts by extremists to foment sectarian tensions with its large Shia community, including a deadly shooting in November.

The interior ministry said a suicide bomber detonated a bomb at the mosque in Shia-majority Qatif, SPA news agency reported.

“An individual detonated a bomb he was wearing under his clothes during Friday prayers at Ali Ibn Abi Taleb mosque in Kudeih in Qatif province,” the ministry spokesman said in a statement.

Qatif hospital issued an urgent call for blood donations after the attack and called in off-duty staff to cope with the high number of casualties, the activist said.

Naseema Assada, a resident of Qatif, said worshippers were celebrating the birth of revered Imam Hussein when the blast occurred.

“The people are very angry,” she said, adding that they tried to stop police from entering the Kudeih area. Residents had feared such an attack was coming, she said, because the government was failing to curb hate speech on social media against the Shia community.

“We don't want a repeat of what is happening in Syria or Iraq here. This is our country and we love it. “The mufti of Saudi Arabia, the highest-ranking Sunni cleric, denounced the attack in a statement broadcast on state television. “It is a criminal act aimed at dividing the sons of the nation... and at sowing trouble in our country,” he said.

Islamic State claims responsibility

The Islamic State group said in an online statement that it had carried out the deadly suicide bomb attack in Saudi Arabia.

The statement said “the soldiers of the Caliphate” were behind the attack by a suicide bomber “who detonated an explosives belt” in the mosque in the Shiite-majority city of Qatif.

It identified the bomber as Abu Amer al-Najdi, and published a picture of him.

Lebonan holds Saudi Arabia 'totally responsible'

Lebanon's powerful Hezbollah movement said on Friday that Saudi Arabia was “totally responsible” for a suicide bombing at the mosque in the Gulf kingdom.

“Hezbollah holds Saudi authorities totally responsible for this ugly crime,” the group said in a statement condemning the bombing.

It accused the ultra-conservative kingdom of “sponsoring and backing criminal murderers” and of “failing to protect” its citizens who have long complained of marginalisation.

Hunt is on

The interior ministry spokesman said Saudi Arabia would “hunt down anyone involved in this terrorist crime carried out by people seeking to undermine national unity. “The website of Arryadh newspaper posted pictures showing bloodied prayer rugs and part of the ceiling of the mosque that had caved in.

Kudeih is in the oil-rich Eastern Province, home to most of Saudi Arabia's minority Shia community which has long complained of marginalisation in the Sunni-ruled kingdom.

Saudi police have made a string of arrests in recent months of extremists suspected of plotting attacks aimed at stirring sectarian unrest in the Eastern Province.

Pakistan condemns attack on Saudi mosque

Pakistan on Friday strongly condemned deadly terrorist attack at the mosque in Qadeeh, Saudi Arabia during Friday prayers.

Foreign Office Spokesman Qazi Khalilullah in a statement said the people and government of Pakistan extend their heartfelt sympathies and deepest condolences to the bereaved families and pray for speedy recovery of the injured.

“We share the grief of the brotherly people of the Kingdom of Saudi Arabia over this cowardly and deliberate attack against innocent civilians,” he said.

The spokesman said Pakistan reiterated its condemnation of terrorism in all its forms and manifestations.

Last November, gunmen killed seven Shias, including children, in the eastern town of Al-Dalwa during the commemoration of Ashura, one of the holiest occasions of their faith.

Four men carried out the attack after killing a man from a neighbouring village and stealing his car to use in the shootings, the interior ministry said.

In April, authorities said they arrested 93 jihadists, including 62 suspected of links to the Islamic State group who were plotting attacks to “incite sectarian sedition”.

Since 2011, protests and sporadic attacks on security forces have taken place in Shia areas.

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