RIYADH, Saudi Arabia — A suicide bomber killed six people and injured at least 20 others during midday prayers on Friday at a Shiite mosque in eastern Saudi Arabia, the Interior Ministry said, one of the first potential signs that the country’s intervention in the sectarian conflict in Yemen is escalating tensions at home as well.
Members of the Shiite minority, who make up about 15 percent of the population and live mainly in the oil-rich Eastern Province, have long complained of discrimination by Saudi Arabia’s Sunni majority and clerical establishment.
During Saudi Arabia’s two-month air campaign against the Houthi movement in Yemen, which practices a form of Shiite Islam and receives backing from Saudi Arabia’s regional rival, Iran, imams at Sunni mosques across the country have rallied the public around the war, in part by repeatedly denouncing Shiites as dangerous infidels.
The Saudi Arabian news media has portrayed the Houthis as proxies of Shiite-led Iran and characterized the Yemen campaign as a vital defense against an Iranian incursion.
At the same time, Saudi Arabia’s participation in the American-led military campaign in Iraq and Syria against the Sunni extremists of the Islamic State has raised fears of a backlash from its sympathizers at home. Thousands of Saudis have traveled to join the Islamic State, which follows a puritanical school of Islam that scholars say is similar to that of Saudi Arabia, although Saudi Arabia’s rulers and clerics dispute that.
A posting on Twitter on Friday that purported to come from a Yemeni arm of the Islamic State claimed responsibility for the attack, but it did not include details and its credibility was hard to assess.
Saudi Interior Ministry officials said in interviews this week that they had seen an increase in violence by Sunni extremists, including three separate attacks near the capital, Riyadh, that killed a total of three police officers and injured two others.
But the last major episode of sectarian violence inside the kingdom came six months ago, when a gunman killed eight people in the Shiite village of Dalwa, in the Al Ahsa region of the Eastern Province, at the end of the Shiite holiday of Ashura.
The bombing on Friday took place in the town of Al Qudaih, near the regional center Qatif, also in the Eastern Province. The Qatif area has been the site of sectarian tensions in the aftermath of the Arab Spring revolts four years ago, including sporadic, Shiite-dominated street protests.
Saudi Arabia, in response, has jailed at least two prominent Shiite clerics who have called for political overhauls such as adopting a constitutional monarchy. One firebrand cleric, Sheikh Nimr al-Nimr, has been sentenced to death for his role in leading street protests in Qatif.
In an apparent attempt to tamp down tensions after the attack on Friday, state television broadcast a telephone call from Saudi Arabia’s senior religious authority, the grand mufti, Abdulaziz al-Asheikh, who called the attack a painful and criminal act against the sons of the homeland.
But on social media, some Saudis rushed to blame Iran for the bombing, asserting that it might have been carried out to provoke Shiites in Saudi Arabia to turn against the kingdom.
Jafar al-Shayeb, head of the Qatif Municipal Council and a Shiite community leader, blamed the sectarian discourse that has spread through Saudi Arabia since the start of the air campaign in Yemen. People feel like this is a direct result of the atmosphere that is turning everybody against each other through speeches and media and social media, he said. It will lead young people to sacrifice themselves and kill others in this region, and people are very angry about it.
Frederic Wehrey, an analyst who follows Saudi Arabia at the Carnegie Endowment for International Peace, argued that the tension may persist even after the Yemen campaign. Sectarianism, once you have unleashed it, you can’t bottle back it up, he said. It afflicts people every day.