BAGHDAD — As Satar Jabar mourned the death of his mother last week, three explosions struck the funeral tent, killing nearly 100 people, including his young son and two of his brothers.

“I feel like I lost my life, my home,” Mr. Jabar said as he received mourners in his home Wednesday afternoon in Sadr City, the gritty and sprawling neighborhood where the attack occurred. “They destroyed everything.”

As visitors recited Koranic verses and sipped tea, angry residents gathered around the corner at the site of the attack, with its charred truck and burned buildings, and demanded that the attackers be executed.

“We want to execute them here,” Mr. Jabar said.

The attack on the funeral last weekend was the deadliest single terrorist strike in recent memory in Iraq, and it has consumed Sadr City, home to a vast Shiite underclass loyal to the radical and politically powerful cleric Moktada al-Sadr, with grief. It has also set off waves of anger toward a government that the people here increasingly view as incompetent and corrupt, even illegitimate, adding to the isolation of a Shiite leadership already struggling to contain growing Sunni unrest.