The three attacks came a day after an Iraqi court sentenced to death Ali Hassan al-Majid, widely known as "Chemical Ali," for the slaughter of 182,000 Kurds in 1988.

A suicide bomber blew himself up in the crowded lobby of Baghdad's Al-Mansour Melia hotel, killing at least 12 people, including a Shia lawmaker and some Sunni tribal sheikhs, staff and security officials said.

They said the explosion, which also wounded 21 people, occurred during an informal gathering of local tribal sheikhs at the hotel located on the west bank of the Tigris river.

Security officials confirmed that the meeting was the target of the attack in the hotel, which houses diplomats and some foreign media organisations.

An AFP correspondent said charred bodies of the victims and many of the wounded were lying near the reception desk in the rubble-strewn lobby, and that the ceiling had collapsed on the bodies.

The blast also damaged the stairway and the elevators. Clusters of white ceiling tiles hung from wires over a floor littered with broken glass and chunks of wall.

Patches of blood stained the marble floor while bits of human flesh were left stuck to the concrete pillars. The main stairway of the lobby was pockmarked from shrapnel and ball bearings while the ceiling on the first floor was also damaged.

A group of US and Iraqi troops searched for clues amid the debris as hotel employees watched on.

One employee said a group of five or six tribal sheikhs had come into the lobby and ordered tea. As the employee headed back to the kitchen the explosion went off behind him.

One of those killed was Fassal al-Gawud, an ex-governor of the western Sunni province of Anbar, where several tribal sheikhs have recently allied with US and Iraqi forces against al-Qaeda, according to security officials.

Hussein Shaalan, a Shia MP from the liberal Iraqi National List of former pro-Western premier Iyad Allawi's political bloc and a tribal chief from the central city of Diwaniyah, was also killed along with his son and a bodyguard.

Other victims included Rahim al-Maliki, a poet employed by Iraq's state-run Iraqiyah television, and two Sunni tribal sheikhs. Five more unidentified people were also killed.

Sheikh Mahmud Daham from Anbar, who was in the hotel, said the attack "targeted the tribes that are fighting terrorism."

"Iraq will stay standing, no matter what you do. We are not afraid of you and we are going to continue fighting you," he said amid the wreckage with corpses around him.

The attack came shortly after two other suicide bombings killed another 33 people, mostly policemen, in the north and central regions of the country.

The deadliest strike was in the northern oil refining town of Baiji where 25 people were killed when a bomber ploughed an explosives-laden oil tanker into the police headquarters of the town, a local police officer said.

Another 50 people, mostly civilians, were wounded.

"A suicide bomber driving an oil tanker tried to break into the building but he blew himself up at the gate because he could not get in. It resulted in huge damage to the building," said Police Captain Ahmed Hussein of Baiji.

"All the wounded are civilians from shops near the headquarters, but most of those killed are prisoners and policemen," he said.

Local authorities imposed a full curfew and blocked all roads leading in and out of the town, which is just north of executed dictator Saddam Hussein's hometown of Tikrit.

In central Iraq, in the town of Hilla, a suicide car bomber slammed into a crowd of recruits waiting outside a police academy, killing eight and wounding several dozen.

"The recruits were just a week away from their graduation," said Police Lieutenant Mohammed al-Dulaimi of Hilla police.

An AFP reporter said the attack gouged out a large crater in the middle of the street. A number of nearby buildings, including a school, and many shops were damaged by the blast.

Salim Saleh, the governor of Babil province, who visited the site, blamed the attack on "takfiris" (Sunni extremists).

Hilla has seen regular bomb attacks as Sunni insurgents have targetted Shia pilgrims travelling from Baghdad south to the holy shrine cities of Karbala and Najaf.

Meanwhile, two US soldiers died of wounds sustained in combat in Iraq, the military said Monday, raising the total toll this month to 73.

One soldier died on Saturday after being wounded in a combined attack involving a roadside bomb and small arms fire in east Baghdad, the military said in a statement.