Three separate suicide bombings have killed at least 35 people in Iraq, many of them policemen and prisoners.
Twelve people were killed when a suicide bomber wearing an explosives-packed vest blew himself up inside a central Baghdad hotel used by foreigners and Iraqi officials.
Police said the bomber had walked into the busy lobby of the Mansour Hotel, where Sunni Arab tribal leaders from western Anbar province had gathered for a meeting.
The hotel is near Baghdad's heavily fortified Green Zone and is often used by provincial Iraqi officials visiting the capital. A number of foreigners also live in the hotel, which was thought to be one of the most secure in Baghdad.
Meanwhile, 15 people were killed when a bomber ploughed an explosives-laden oil tanker into the police headquarters of the northern Iraqi town of Baiji. Another 50 people, mostly civilians, were wounded.
Local authorities have imposed a full curfew and blocked all roads leading in or out of the town, which is just north of former dictator Saddam Hussein's hometown of Tikrit. Residents have been warned to stay inside.
The attack in Baiji came about three hours after another early morning bombing in the town of Hilla, south of Baghdad.
There a suicide bomber slammed into a crowd of recruits waiting outside a police academy, killing eight and wounding several dozen.
Those two bombings appear to be the latest assaults on Iraq's fledgling security forces, seen by both the US military and the Iraqi government as the cornerstone of any future stability in the country.
The attacks came one day after Ali Hassan al-Majid, widely known as Chemical Ali, Saddam Hussein's cousin and former defence minister, was sentenced to death for the slaughter of 182,000 Kurds in 1988 by an Iraqi court.
