Suicide bombers killed at least 90 worshipers Friday inside two Shiite Muslim mosques northeast of the capital near the Iranian border, and a pair of car bombs outside a Baghdad hotel that houses foreign journalists destroyed a nearby apartment building and left several more people dead.

In Khanaqin, a mixed Shiite and Kurdish town 80 miles northeast of Baghdad, attackers wearing suicide belts walked into the two mosques and lined up among worshipers gathered for Friday prayers, then detonated their explosives as the imams at both mosques delivered their sermons. In addition to the 90 dead at the mosques, at least 75 worshipers were injured, said Ibrahim Hassan Bajillan, head of the local governing council in Diyala province.

The explosions collapsed the roofs of the Sheikh Murad Mosque and the larger Khanaqin Grand Mosque. Residents rushed to the scenes to search the rubble for victims. But after darkness fell, searchers called off the hunt for bodies for the night. Police said the toll is likely to rise after the search for victims resumes Saturday.

Shiite mosques are a frequent target of attackers in Iraq. Earlier this month, at least 29 people were killed in an attack on a mosque in Musayyib, south of Baghdad. The insurgency in Iraq is led by Sunni Muslims, the most radical of whom regard Shiites as heretics and accuse them of collaborating with U.S. forces.

In the capital, suicide attackers exploded two vehicles loaded with bombs outside the Hamra Hotel early Friday, collapsing at least one neighboring apartment block and shearing off walls around sleeping families.

The back-to-back Baghdad blasts killed at least six and wounded more than 41, police said. At least two children were among the dead, police said. There were no immediate reports of foreign casualties.

The attackers appeared to follow a pattern used in a suicide car bomb attack last month on the larger Palestine Hotel. In that Oct. 24 attack, one of three vehicles blew a hole in a concrete blast wall to clear the way for an explosives-laden cement truck to drive into the hotel. But the truck exploded prematurely when U.S. troops opened fire on it. The attack killed 17 Iraqis, but the death toll could have been far higher if the plan had succeeded. The Palestine Hotel houses the Associated Press, Fox News and other media organizations.

Outside the Hamra, rescue crews pulled wailing children off the rubble and pulled dust-shrouded dead and wounded from under twisted girders and broken masonry. Screaming women in black abayas and other survivors sought family members as cars set alight by the blast burned around them.

Hotel security cameras caught the first attacker as he drove up in what appeared to be a white minivan. The vehicle detonated just outside blast walls surrounding the hotel.

A second vehicle attempted to drive through a hole made in the walls by the first blast, but its way was blocked by a deep crater and rubble left by the explosion. The second vehicle then detonated before it could get through. The second explosion, more powerful than the first, destroyed the security camera.

American officers and Iraqi police said the second car bomb was carried by a water truck.

Iraqi and U.S. authorities said they believed the second bomb was meant to target the hotel itself. Among the news organizations based at the Hamra are NBC News and the Boston Globe.

The blasts hurled body parts into the hotel courtyard and swimming pool.

A U.S. military statement said the first vehicle, a 16-passenger van, carried about 400 pounds of explosives. The water truck carried about 1,000 pounds of explosives, it said. In addition to the apartment building near the Hamra Hotel, the blasts damaged other buildings in the area and wrecked at least 30 vehicles, the statement said.

U.S. soldiers from Task Force Baghdad participated in search-and-rescue operations after the explosions, and American medics administered first aid and helped evacuate the more seriously wounded to local hospitals.

Al Qaeda in Iraq, a group led by Jordanian militant Abu Musab Zarqawi, claimed responsibility for the blasts, saying it had struck with three vehicle bombs. A third car bomb was discovered nearby and destroyed by security officials, apparently after release of the al Qaeda in Iraq statement.

Mike Boettcher of NBC News, who was in the Hamra at the time, said the first car bomb detonated at 8:12 a.m., and "we were blown out of our beds," the Associated Press reported.

He said on the "Today" show that the resulting hole in the blast walls was too small for the second vehicle, which exploded outside the barrier, causing great destruction in the neighborhood.

"We got down on the floor and crawled, and then the second bomb hit, and we were blown back," Boettcher said. The blast walls "saved our lives," he said.

"I woke up to a huge explosion which broke all the glass and displaced all the window and doors frames," said Saab Izzi, an Iraqi journalist with the Boston Globe, AP reported.

There was some speculation at first that the target was a nearby Interior Ministry building where U.S. troops Sunday found about 170 detainees in a secret underground bunker formerly used as a bomb shelter. Some of the detainees appeared to have been mistreated, and the Iraqi government launched an investigation. Interior Ministry officials said, however, that the hotel, not the ministry building, was the target.

Barbash and Branigin reported from Washington. Special correspondent Hassan Shammari contributed to this article.