Najaf, Iraq ? In a blow to radical Shiite cleric Muqtada al-Sadr’s militia, U.S. soldiers captured his key lieutenant during a raid early Wednesday that left 24 people dead.

Coalition officials said they seized Riyadh al-Nouri, the cleric’s brother-in-law, and detained three others in an operation that involved hundreds of U.S. soldiers and dozens of tanks. In addition to the dead, nearly 50 people were wounded, hospital and militia officials told The Associated Press.

Hours later, Iraq’s national security adviser, Mouwafak al-Rubaie, said that al-Sadr had agreed to withdraw his militia from Najaf and hand the city back to Iraqi police, raising hopes for an end to weeks of conflict, the Associated Press reported. Al-Rubaie said al-Sadr made the offer in a letter to the city’s Shiite clerical hierarchy.

Al-Sadr offered to remove his fighters from Najaf — except for those who live there — but demanded that U.S. and other coalition troops “return to base,” al-Rubaie said. Al-Sadr has reportedly made a number of such offers since the start of the uprising in early April, all of which failed to lead to an end to the confrontation.

But the latest offer came shortly after Wednesday’s raids, which were seen as a clear U.S. message that the coalition had extended its reach well into the city. The arrest of al-Nouri also was a blow to al-Sadr and his organization.

Brig. Gen. Mark Kimmitt, coalition deputy chief of operations, said al-Nouri would be handed over to Iraqi authorities for prosecution.

“We still are committed to finding a peaceful resolution to this problem,” Kimmitt told reporters in Baghdad. “But until that peaceful resolution comes forward … we will continue to conduct military operations directed against his forces.”

The raid began about 2 a.m., when most of the city’s residents were asleep and the streets were left to howling dogs and rumbling Abrams tanks and Humvees.

As U.S. troops made their way deeper into the city, gunfire erupted in several neighborhoods and grenade explosions echoed for miles.

In this environment moved the swift scouts from Apache Company of the 2nd Battalion, 37th Armored Regiment of the 2nd Armored Cavalry. Their convoy of tanks and Humvees rolled along deserted streets, reaching an oil slick on a desolate stretch, where a guerrilla fired an RPG round and tank gunners fired back.

Al-Nouri was captured in his home about 4 a.m., the Associated Press reported. He offered no resistance as he was arrested, the military said.

Iraqi children run away from a burning street barricade at the entrance to the suburb of Sadr City, Baghdad, Iraq. The neighborhood has a large support base for radical Shiite cleric Muqtada al-Sadr, who lost key aide Riyadh al-Nouri when U.S. troops seized al-Nouri on Wednesday.