BAGHDAD, Iraq - A U.S. military helicopter carrying two pilots crashed north of Baghdad today, a day after a spate of suicide attacks left nearly three dozen people dead in northern Iraq.

An AH-64 Apache helicopter crashed in Mishahda, 20 miles north of the capital, an Associated Press reporter at the scene said. The helicopter was in flames on the ground. There were no immediate reports of casualties.

The U.S. military confirmed that a helicopter carrying two pilots crashed near Baghdad. The crash was under investigation and a recovery team was determining the status of the pilots, the military said.

A roadside bomb in Baghdad exploded near a police patrol at Antar Square in the capital's northern Azamiyah neighborhood, police 1st Lt. Mohammed al-Hayali said. Two people were killed, he said.

The attack followed three suicide bombers who struck a police headquarters, an army base and a hospital around Mosul on Sunday, killing 33 people in a setback to efforts to rebuild the northern city's police force that was riven by intimidation from insurgents seven months ago.

Abu Musab al-Zarqawi's al-Qaida in Iraq claimed responsibility for the attacks in Mosul - the country's third-largest city. The claim, which was made on an Internet site used by militants, could not be verified.

The relentless carnage has killed at least 1,338 people since April 28, when Prime Minister Ibrahim al-Jaafari announced his Shiite-dominated government. With the Sunni Arab-dominated insurgency targeting the Shiite majority, the wave of killings has raised fears of a possible civil war.

The violence has continued despite repeated crackdowns and U.S.-led offensives on insurgent strongholds throughout the country, showing that militants have the depth and resilience to pin down a large U.S. military contingent as well as a fledgling Iraqi security forces.

At least 18 other people were killed in attacks elsewhere in Iraq on Sunday, including a U.S. soldier whose convoy was hit by a roadside bomb in Baghdad and six Iraqi soldiers who were gunned down outside their base north of the capital.

Today, Iraqi police detained 48 suspected insurgents in Iskandriyah, Jibbala and Haswa in northern Hillah, police Capt. Muthana Khalid said. The three-day raid, which ended early today, took place in an area south of Baghdad, part of "Operation Lightning." Police also seized weapons and a potential car bomb.