BAGHDAD - A suicide car bomb devastated a Shiite mosque in northern Iraq, one of a series of attacks Friday that killed at least 37 Shiite pilgrims and worshippers, police and medical officials said.
The incidents are the latest in a series that have targeted Shiites, raising concerns that insurgents are stepping up attacks, hoping to re-ignite sectarian violence that nearly tore the country apart in 2006 and 2007.
Though violence has dramatically declined in Iraq in the past two years, U.S. officials have repeatedly called the security gains fragile and cautioned that a waning insurgency still has the ability to pull off sporadic, high profile attacks.
The deadliest blast occurred in Rasheediyah, north of Mosul, when a suicide car bomb struck a mosque, killing at least 30 people and trapping dozens more underneath the rubble, said a police official in Ninevah operations command.
The official said at least 88 were injured in the blast. Bodies were still being pulled from the rubble, the official said.
It was the second deadliest attack since U.S. forces withdrew from cities as part of a U.S.-Iraqi security pact that maps out the complete withdrawal of American troops by the end of 2011.
The attack occurred shortly after 1 p.m. as worshippers were leaving Friday prayers. The blast also severely damaged a dozen other buildings near the mosque, the official said.
In Baghdad, roadside bombs targeted pilgrims returning from the southern holy city of Karbala where hundreds of thousands of devout Shiites gathered to celebrate the birth of Mohammed al-Mahdi, the 12th Shiite imam, who disappeared in the ninth century.
Devout Shiites call him the Hidden Imam and believe he will return to restore peace and harmony. The ceremonies concluded early Friday morning.
The first of three bombs exploded at about 9:10 a.m., targeting a minibus with pilgrims as it entered the Shiite slum of Sadr City, a police official said. The blast killed four pilgrims and wounded eight others, the official said. The causalities were confirmed by a medical official.
A short time later, two near simultaneous explosions near the Shaab football stadium in eastern Baghdad killed three pilgrims as they were walking home to Sadr City, said another police official.
Thirteen pilgrims also were wounded in the two blasts, which occurred less than half a mile apart, the official said.
All the officials spoke on condition of anonymity because they were not authorized to release information to the media.
The blasts came a day after a roadside bomb targeted pilgrims on their way to Karbala, killing one and wounding four others.
Last Friday, a string of bombings targeted Shiite mosques in the Baghdad area during prayers, killing at least 29 people.
No group has claimed responsibility for the attacks. Attacks on Shiite civilians -- particularly during pilgrimages -- have been the hallmark of Sunni extremists, including al Qaeda in Iraq.
While overall attacks are down in Iraq, armed robberies targeting jewelry stores, currency exchanges and banks appear to be on the rise.
Gunmen broke into a goldsmith shop in the western Baghdad district of Baiyaa on Thursday, killing the owner and making off with an unknown quantity of gold, two Iraqi police officials said Friday.
One interior ministry official disputed the robbery, saying no gold was stolen and gunmen targeted the owner in a drive-by shooting.
The officials spoke on condition of anonymity because they were not authorized to talk to the media.
The robbery follows a bank heist last month in Baghdad where gunmen killed eight security guards and made off with millions of dollars. Iraqi authorities have said they arrested the gunmen and recovered all the money.
Iraqi Vice-President Adel Abdul-Mahdi said in a statement this week that one of those alleged gunmen served as one of his bodyguards and eight others were soldiers in the Iraqi army.
