Two car bombings in Baghdad have left at least eight people dead and 17 injured.
The first bombing, at 6.15am (0215 GMT) on Monday, targeted the Sadir hotel in central Baghdad, which is used by foreign security personnel.
A bomber blew up a minivan packed with explosives at a checkpoint at the gates to the hotel - which has been bombed in the past - killing six people and wounding 16, Iraqi journalist Walid Khalid told Aljazeera.
Witnesses said the explosion was followed by the sound of automatic weapons fire.
Most of the casualties were Iraqi private security guards employed by the hotel.
At 8.30am (0430 GMT), a second car bomb targeted a police commando patrol under the Harithiya bridge in the west of the city, killing three policemen and wounding 11, Khalid added.
Also on Monday, gunmen killed a family of four as they waited on the street for a ride in the tense city of Samarra, 95km north of Baghdad.
Police said Subhi Thamir Husayn al-Badri, his wife and two sons were shot dead in the Jiriya district, adding that the reason for the killing was unclear.
Website
In March, Abu Musab al-Zarqawi's al-Qaida in Iraq purportedly posted a video on a website showing a huge explosion at the Sadir hotel, killing four and wounding 40, including 30 American contractors.
Al-Zarqawi's group in its posting had described the Sadir as the "hotel of the Jew".
Car bombs have become the most lethal tactic in Iraq's violence. A truck bomb packed with 230kg of explosives on Sunday killed 39 people outside a Baghdad police station.
US accepts Polish plans to exit Iraq
The United States had accepted Poland's plans to withdraw most of its 1700 troops from Iraq at the beginning of next year, Polish President Aleksander Kwasniewski says.
Poland, one of Washington's biggest European allies in Iraq, runs a multinational stabilisation zone south of Baghdad.
"The current rotation in Iraq will be the last one. By the end of January, we would like to pull the troops and replace them with smaller groups, which could, for example, help train the Iraqi army," Kwasniewski told public radio.
Kwasniewski said his country's plan to make the shift ending its mission in January the last one had been accepted by the allies. He said the move was the subject of talks between Defence Minister Jerzy Szmajdzinski and US Secretary of Defence Donald Rumsfeld on 19 July.
Kwasniewski said he wanted to leave setting an exact withdrawal schedule for the next government and president, to be picked in elections due in September and October.
The centre-right opposition, tipped to win parliamentary elections, has supported Poland's presence in Iraq and accused the ruling leftists of pledging to withdraw only to drum up its support ratings ahead of the polls.
Australian PM visit
Meanwhile, Australian Prime Minister John Howard arrived in Baghdad on Monday for a surprise visit and talks with the new government.
Howard was meeting Prime Minister Ibrahim al-Jaafari, the government press office said. He is also expected to meet some of the 750 Australian soldiers in Iraq.
About half the Australian force is in southern Iraq helping train Iraqi security forces and protecting Japanese military engineers working on reconstruction projects.
Howard, who had been visiting Britain, has been among the strongest supporters of the US-led operation in Iraq.
Australian soldiers fought in the US-led invasion launched in March 2003.
The Australian leader recently met US President George Bush in Washington and British Prime Minister Tony Blair in London.
PHOTO CAPTION
Iraq and U.S. soldiers search the scene of a suicide truck bomber in front of the Rashad police station (not seen) Sunday, in the eastern neighborhood of Mashtal, Baghdad. (AP)