About 200 Shiites rallied outside the Green Zone on Monday to demand that U.S. and Iraqi forces do more to stop insurgent attacks in the capital and help Iraqis who are fleeing their homes because of sectarian violence.

Most of the protesters were women dressed in abaya, the full-length black robes worn by devout Muslim women. One weeping demonstrator held up the photo ID card of her husband, a truck driver, and said he recently had been killed in a drive-by shooting.

Other protesters waved large cloth banners with slogans demanding that the Iraqi government provide better care for displaced families.

The rally took place outside the tall cement wall surrounding the Green Zone, where Iraq's government meets and the U.S. and British embassies are located. At one point, two Iraqi men — a soldier and a civilian — left the compound to meet with the protesters and briefly take notes about who they were and what they were demanding.

Meanwhile, the bullet-ridden, handcuffed and blindfolded bodies of three Iraqi men were found in Baghdad's southern neighborhood of Dora, said police Capt. Jamil Hussein said. A drive-by shooting also killed a Shiite grocer was killed in his shop, Hussein said.

Elsewhere, three roadside bombs exploded in Baghdad on Monday, a national holiday in Iraq, wounding two Iraqi civilians, police said.

The first bomb exploded at 8 a.m. in the Mashtal district of eastern Baghdad, wounding two Iraqi civilians, said police Maj. Mahir Musa.

The second blast, targeting an Iraqi police convoy, occurred at 9:45 a.m. on a highway in the nearby district of Kamsara, causing no casualties, said police Lt. Bilal Ali Majid.

About five minutes later, a fuel can being used as a roadside bomb exploded about 500 meters (yards) behind a U.S. military convoy in Al-Bayaa, a neighborhood of southern Baghdad, causing no injuries or damage, the U.S. military said.

May 1, known as Workers' Day, is a national holiday that closes government offices across Iraq, but many businesses and stores work normal hours.

Tens of thousands of Iraqis have fled their homes in mixed Sunni-Shiite areas because of sectarian violence, some of it caused by militias allied with Iraqi political parties. A surge in such attacks began after the Feb. 22 bombing of a Shiite shrine in Samarra in northern Iraq.

In other violence Monday:

— Insurgents fired two mortar shells at a U.S. military base in Haqlaniyah, 220 kilometers (140 miles) northwest of Baghdad, prompting soldiers to search surrounding houses and shops for suspected militants, witnesses said. No casualties were reported.

— In Tikrit, the hometown of former dictator Saddam Hussein, roadside bombs aimed at American convoys exploded in two nearby neighborhoods, police said. No casualties were reported, but U.S. and Iraqi forces to searched homes in both areas.

On Sunday, a roadside bomb in Tikrit, which is 130 kilometers (80 miles) north of Baghdad, destroyed an American Humvee, the military said. It said no service members were killed in the attack, but did not say whether anyone was injured.