Baghdad ? Twin car bombs ravaged a popular shopping area in Baghdad’s biggest Shiite district Wednesday, killing at least 41 people in another powerful strike by suspected Sunni insurgents seeking a return to sectarian chaos.

In less than a week, blasts have struck the heart of Shiite traditions and unity: hitting Shiite pilgrims, a revered shrine and now teeming Sadr City in attacks that have claimed nearly 200 lives.

The once-powerful Shiite militias have so far largely held back from retaliations — and reopening memories of the back-and-forth bloodshed from Iraq’s 2006-7 sectarian slaughters.

It was the deadliest bombing attack inside sprawling Sadr City since U.S.-backed Iraqi forces seized control of the area in late May. The offensive broke the hold of the feared Mahdi Army, a network of Shiite militiamen loyal to anti-U.S. cleric Muqtada al-Sadr.