BAGHDAD, Iraq — Iraq’s prime minister sharply criticized a American-Iraqi attack yesterday on a Shiite militia stronghold in Baghdad, breaking with his American partners on security tactics as America launches a major operation to secure the capital.

More than 30 people were killed or found dead yesterday, including 10 paramilitary commandos slain when a suicide driver detonated a truck at the regional headquarters of the Shiite-led Interior Ministry police in a mostly Sunni city north of Baghdad.

Prime Minister al-Maliki’s criticism followed a pre-dawn air and ground attack on an area of Sadr City, the stronghold of the radical Shiite cleric Muqtada al-Sadr and his Mahdi Army militia.

Police said three people, including a woman and a child, were killed in the raid, which the American command said was aimed at “individuals involved in punishment and torture cell activities.” One American soldier was wounded, America said.

A Shiite, Mr. Maliki said he was “very angered and pained” by the operation, warning that it could undermine his efforts toward national reconciliation.

“Reconciliation cannot go hand in hand with operations that violate the rights of citizens this way,” Mr. Maliki said in a statement on government television. “This operation used weapons that are unreasonable to detain someone — like using planes.”

He apologized to the Iraqi people for the operation and said, “This won’t happen again.”

Friction between the American military and the Iraqi government emerged as the American military kicks off an operation to secure Baghdad streets after a surge in Sunni-Shiite violence — much of it blamed on Mr. Sadr’s militia. Mr. Sadr has emerged as a major figure in the majority Shiite community and a pillar of support for Mr. Maliki.

After the Sadr City attack, President Talabani, who is a Kurd, met with the top American commander in Iraq, General George Casey Jr., to discuss security operations in Baghdad. Mr. Talabani said he told General Casey “it is in no one’s interest to have a confrontation” with Mr. Sadr’s movement.

Speaking to reporters after the meeting, General Casey made no mention of Mr. Sadr but said he had discussed plans with Mr. Talabani to bring “fundamental change to the security situation in Baghdad.”

General Casey said he hoped the new operation would “change the situation significantly prior to Ramadan,” which begins in late September.

“To do that, it will take the cooperation not only between the Iraqi security forces and the coalition but with all of the people in Baghdad working together to combat terrorism,” General Casey said. “All the security operations are designed to protect the population.”

But the public position taken by Messrs. Maliki and Talabani signaled serious differences between Iraqi politicians and both American and Iraqi military officials on how to restore order and deal with armed groups, many of which have links to political parties.