BAGHDAD, Iraq (CNN) -- Al Qaeda in Iraq is planning suicide attacks against Iraqis in Baghdad "in the near future," the U.S. military warned Friday.

An Iraqi boy peers from behind the bullet-riddled door of his home in Baghdad's Sadr City on April 18.

Information collected by coalition forces indicated that "numerous terrorists" had entered the Baghdad area to carry out attacks using vehicle-borne improvised explosive devices or suicide vests, according to a statement from the Multi-National Corps-Iraq. No details were provided.

One or more of the attacks were expected to target the Karkh district of Baghdad, where a car bomb exploded in March 2005 near the Sunni mosque Ibn Tamiya. The mosque is on the dangerous road leading to the Baghdad airport. There were no reports of casualties.

Iraqis were being warned to be vigilant for signs of terrorist activity and asked to report any unusual signs through tip lines or troops in their area.

Iraqi Security Forces and Coalition Forces were distributing pamphlets describing signs that may indicate terrorist activity.

Brig. Gen. Qassim Atta, the spokesman for the Baghdad security plan, warned listeners Friday during the main newscast on al-Iraqia state TV.

Reiterating what the U.S. military said about credible intelligence indicating that suicide, vehicle and IED attacks are being planned by "terrorist groups," Atta asked people to be cautious and wary.

He asked them to call the Iraqi Security Forces and the hot lines for the ministries of Defense and Interior and the Baghdad security plan hot lines to report anything suspicious.

Indications of a possible suicide-vest attack include people displaying abnormal behavior such as an agitated demeanor and wearing inappropriate clothing for the weather.

Signs of a possible vehicle-borne improvised explosive attack are unfamiliar vehicles driving repeatedly around crowded areas, people taking videos or photos of these areas, cars without license plates or multiple fuel cans in the seat or trunk of a vehicle. Attackers also might use a stolen ambulance.

The Multi-National Corps-Iraq statement said that historically, al Qaeda in Iraq attacked large gatherings of people: funerals, markets and checkpoints.

"Wall barriers emplaced by the government of Iraq and Coalition Forces have been largely successful in protecting neighborhoods, markets and roadways. However, AQI are constantly seeking opportunities to harm innocent Iraqi civilians," it said.

Recently, al Qaeda in Iraq began targeting Sons of Iraq and Awakening groups, because those organizations have taken away their support zones and havens. Awakening Councils, or Sons of Iraq, are Sunni groups that have turned against al Qaeda in Iraq.

"Make no mistake, Al Qaeda in Iraq is still present," said Maj. Gen. Jeffery Hammond, commanding general of Multi-National Division-Baghdad.

"We have disrupted their organization, but they still seek to subjugate and intimidate the Iraqi people," he said in the statement. "The Sons of Iraq and ISF are heroically standing against such attacks directed against them and their families."

The U.S. warning came on the same day an Interior Ministry official said at least seven people were killed in intense fighting between Iraqi Security Forces and Mehdi Army militiamen loyal to cleric Muqtada al-Sadr in the Baghdad neighborhood of Sadr City.

The interior official said 62 people -- including women and children -- were wounded, while hospital officials in Sadr City put the number at 72.

In another incident, two children were killed by a roadside bomb while collecting firewood in Tarmiya, about 25 miles (40 km) north of Baghdad, about noon Friday, the U.S. military said. U.S. officials said the attack was probably targeting Awakening Councils, or Sons of Iraq -- Sunni groups who have turned against al Qaeda in Iraq.

Also, a roadside bomb in the Diyala town of Khalis struck a minibus, killing six members of an extended family -- two of them brothers -- Friday afternoon, a medical source in the province confirmed.

In the Sadr City violence, the militia used rockets and mortars, in addition to small arms fire, the official said. A fire broke out in Jamila Market, where dozens of shops were destroyed last month during an indirect attack.

However, a U.S. military spokesman in Baghdad said he wouldn't describe the situation as intense fighting.

"There has been sporadic gunfire, harassment fire, taking place all day," said Lt. Col. Steve Stover.

He confirmed the death of a "criminal" who was killed while planting an explosive. "Other than that, nothing spectacular and nothing the ISF couldn't handle."

Clashes also broke out Friday evening in the Shiite enclave of Abu Dsheer in the predominantly Sunni district of Dora in southern Baghdad, where Mehdi fighters clashed with Iraqi security forces backed by U.S. troops. At least three people were wounded, and an infirmary was set ablaze during the fighting, according to the official.

According to Sadr City residents, the Mehdi Army used loudspeakers at mosques Thursday to warn Iraqi security forces to avoid the area, saying the Mehdi Army was unbeatable. E-mail to a friend

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