BAGHDAD, Iraq — Suicide bombers killed nearly 100 people Friday in one of the deadliest days of Iraq's insurgency, bringing houses down on sleeping families in Baghdad near a hotel that houses Westerners and shredding Shiite Muslim worshipers in two mosques in the eastern part of the country just as the victims turned their faces up to the preachers to hear their Friday sermons.

"We had just said 'God is Great' — and then I felt nothing but a massive explosion," Mohammed Kofiq Akram said by telephone from a hospital in Khanaqin, the northeastern town where most of the deaths occurred. Akram said shrapnel had blasted his head and right shoulder.

At least 90 people were killed in the two mosques, according to Ibrahim Hassan Bajillan, head of the governing council for Diyala province. In both buildings, witnesses said, the explosions came just as worshippers were settling themselves on the floor to listen to their imams after finishing ritual prayers.

In Baghdad, there were no casualties in a hotel that Iraqi police and U.S. soldiers said was the target of two successive bombings. But the explosions leveled the simple houses outside the hotel's blast walls, killing at least eight people.

In the aftermath of the Baghdad blasts, emergency workers scooped a wailing, bleeding girl of about 8 or 9 off a mound of rubble from a collapsed apartment building while twisted vehicles burned and firefighters clawed with their hands to reach trapped families. "My son! My son!" one woman screamed, collapsing in the arms of a ring of women in black abayas. The boy had been crushed to death.

Nationwide, the attacks were the deadliest since Sept. 14, when at least 14 insurgent bombings in Baghdad killed more than 160 people. Al-Qaida in Iraq was believed to have been involved in at least the Baghdad blasts on Friday. The insurgent group said in a statement that the bombings represented retaliation for a U.S. military offensive still under way in far western Iraq.

As in the September attacks, most victims Friday were civilians.

The same ruthless frequency of attacks that has dulled international attention to the carnage in Iraq has made Baghdad's emergency workers briskly efficient. Firefighters, sweating from exertion despite the coolness of the autumn morning, ferried oxygen and water to a man trapped under what had been the top floor of his home.

"Go! Go!" watching men exhorted.

The rescue fixated the neighborhood for more than an hour while other firefighters pulled one or two contorted, flopping corpses from nearby apartments.

When the survivor proved to be a Sudanese Arab — a member of a group mistrusted by many in Iraq — the neighbors watched silently. No cheers went up as rescuers carried the man on a stretcher down the hill of broken masonry, his body almost miraculously spared injury and his head twisting as he craned to see the destruction.