BAGHDAD, Iraq (CNN) -- Iraqi political and military leaders and U.S. military commanders have traveled to the northern Iraqi city of Mosul ahead of a planned offensive on al Qaeda in Iraq loyalists, according to a senior U.S. military source.
Saturday's meeting portends a major confrontation between U.S. and Iraqi troops and al Qaeda in Iraq militants, who have a strong presence in the diverse, sprawling city of Mosul, the capital of Nineveh province -- a region long beset by conflict.
Iraq's Defense Ministry last Sunday announced a major movement of Iraqi forces to Mosul as a prelude to an offensive aimed at clearing the region of Islamic fighters loyal to al Qaeda in Iraq.
The U.S. source in Iraq said Saturday that more Iraqi troops will be moving into Nineveh over the next few days in preparation for additional operations.
The source said "Iraqis are in the lead in this action."
In Baghdad on Saturday, weeping relatives buried dozens of victims of the deadliest bombings since the U.S. troop surge began last spring.
Iraqi officials raised the death toll of Friday's attacks to at least 99, according to The Associated Press. At least 62 people were killed at the central al-Ghazl market along with 37 others shortly afterward at the New Baghdad area pigeon market, they said.
A top Iraqi government official said two mentally disabled women were strapped with explosives and sent into the busy Baghdad markets, where they were blown up by remote control. Watch how the use of the women represents a new tactic »
U.S. military officials, however, referred to both attacks as suicide bombings, saying both women detonated their explosive devices.
On Friday the U.S. officials attributed the attack to al Qaeda in Iraq and made no reference to the mental conditions of the women.
However, on Saturday, Maj. Gen. Jeffery Hammond, commander of Multi-National Division-Baghdad, said "there are some indications that these women were handicapped."
A CNN producer who was permitted to view pictures of the dead bombers said they appeared to have Down syndrome features.
Witnesses said the bomber at the southeastern market had brought caged birds to the bazaar on Friday and people gathered to look at them before her hidden vest exploded.
"From what I see, it appears that the suicide bombers were not willing martyrs," Hammond said. "They were used by al Qaeda for these horrific attacks."
The U.S. military gave lower casualty figures than the Iraqi officials -- 27 dead and 53 wounded.
Traveling to Mosul for the meeting ahead of the offensive were Iraqi Prime Minister Nuri al-Maliki; Iraqi Defense Minister Abdul Qadir Mohammed Jassim; Iraqi Interior Minister Jawad al-Bolani; U.S. Gen. David Petraeus, commander, Multi-National Forces-Iraq; and Lt. Gen. Raymond Odierno, commander, Multi-National Corps-Iraq.
They met Lt. Gen. Riyadh Jalal Tawfiq, commander, Ninevah Operations Command; Maj. Gen. Mark Hertling, commander, Multi-National Division-North' Brig. Gen. Tony Thomas, deputy commander, MND-North; and other senior leaders in Nineveh province and throughout Iraq.
The source said the officials would be briefed on "the security situation in that city [Mosul] and Nineveh province, and the continuation of operations in the northern provinces" from the top Iraqi and U.S. commanders in the region.
The stepped-up effort in Mosul is part of Operation Iron Harvest, the U.S.-led offensive in Nineveh, Diyala, Tameem, and Salaheddin provinces that kicked off last month.
A hotbed of fighting and tension between insurgents and security forces, Mosul has been a destination for insurgents crossing into Iraq from Syria.
Last week, a deadly blast at a residential building in Mosul and an attack the next day that killed the head of Nineveh's police prompted Iraqi officials to redouble attention on the city -- where al Qaeda in Iraq has had a strong presence.
Al-Maliki, who has recently broached the issue of confronting militants there, called for a "decisive" confrontation with al Qaeda in Iraq militants and the deployment of more Iraqi troops.
Last week, Interior Ministry spokesman Maj. Gen. Abdul Karim Khalaf said that orders were issued to expand Iraq's police and army presence in the city, that there is a "big job" ahead, and an operation will be launched in coming weeks.
"Our intelligence has infiltrated al Qaeda," Khalaf said.
Meanwhile, a roadside bomb blast hit an Iraqi police patrol near the northern Iraq city of Tikrit on Saturday, killing four Iraqi police officers, according to a Tikrit police official. The attack happened in Shirqat, north of Tikrit, the official said.
Police fought with al Qaeda members in Samarra, a city in northern Iraq's Salaheddin province, Friday night, according to a Samarra police official.
Two police officers were wounded, and four suspected al Qaeda members were killed, the official said.
In eastern Baghdad, gunmen shot dead two members of a top academic's security detail, an Interior Ministry official told CNN.
The shooters were in vehicles themselves when they opened fire on the cars of the deputy dean of Baghdad University's School of Medicine, Dr. Abdul Karim al-Mohammedawi.
Two security officers were killed and two others were wounded and the gunmen fled. Al-Mohammedawi escaped unharmed in the attack, which took place near al-Shaab Stadium about 3:30 p.m. E-mail to a friend
CNN's Cal Perry and Jomana Karadsheh contributed to this report.