BAGHDAD, Iraq – U.S. and Iraqi troops clashed with gunmen firing heavy weapons from concrete high-rises in a Sunni insurgent stronghold north of the heavily fortified Green Zone on Wednesday.

Apache attack helicopters buzzed past the tall buildings and radio towers, with several Humvees on the tree-lined street below. Gunfire rang in the background as shells fell, according to AP Television News footage.

Black smoke rose from the area, on the west bank of the Tigris River about one mile north of the Green Zone, site of the U.S. and British embassies as well as the Iraqi government headquarters.

The clashes were the second major fighting to break out in the area in less than a month.

There were conflicting numbers of insurgents reported killed and captured in the fighting, which began before dawn. Iraq’s Defense Ministry spokesman Mohammed al-Askari told The Associated Press 30 insurgents were killed and 27 were arrested, including four Egyptians and a Sudanese man.

The U.S. military said seven suspected insurgents were detained and rocket-propelled grenades, anti-tank rounds and 155 mm artillery rounds were seized. The American statement did not mention deaths.

The military reported separately that an American soldier was killed Wednesday near the city’s center. Officials declined to give more specifics. The miliary also said that two Marines were killed Tuesday in western Anbar province.