At least 22 people have been killed and 30 injured in a car bombing at a market in southern Baghdad, Iraqi police say.
Doura is considered one of Baghdad's most dangerous areas
Correspondents say the blast in the al-Doura area, apparently aimed at a police patrol, is the deadliest car bombing in the capital in weeks.
The market was mostly used by Shia Muslims.
The blast came as visiting UK Foreign Secretary Jack Straw urged Iraqi leaders to put aside sectarianism to form a government of national unity.
Doura is considered one of the most dangerous areas of the capital, with bombings a regular occurrence since the Sunni Arab-dominated militant insurgency began in 2003.
The explosion, which police said was detonated by remote control, left a number of cars and shops ablaze at the Abu Dshir general market.
Witnesses said some of the dead were passing motorists.
Women were reported to be screaming "Our children have died" and "The terrorists, may God punish them."
In other developments on Tuesday:
- Jordanian embassy driver Mahmoud Suleiman Saidat, who was kidnapped in Baghdad on 20 December and appeared on Arab TV stations pleading for his release, is set free by his abductors
- Saad Jarallah, a spokesman for the Sunni Arab political group the National Dialogue Council, is found dead with multiple gunshot wounds, three days after his disappearance
- Two police commandos are killed and four other people wounded in a roadside bombing in southern Baghdad
- A civilian dies in a gun attack against a judge in Baquba, 65km (40 miles) north of Baghdad; the judge is wounded.
Tuesday's market blast came as Mr Straw held talks with Shia, Sunni Arab and Kurd leaders amid slow progress in forming a new coalition government.
Shia leaders say they have the right to control key posts after winning 128 of the 275 seats in parliament after December's elections.
RISE IN INSURGENT ATTACKS
Total attacks: 26,496
Improvised bombs: 5,607
Car bombings: 420
Suicide car bombings: 133
Suicide bombers wearing explosive vests: 7
Total attacks: 34131
Improvised bombs: 10,593
Car bombings: 873
Suicide car bombings: 411
Suicide bombers wearing explosive vests: 67
But Sunni Arab leaders want to ensure they are represented at a senior level, and are seeking to break the control of Shia militias on the interior ministry.
Following talks with President Jalal Talabani, Mr Straw said Iraqis wanted a government that bound together different segments of society.
The US warned that aid to Iraq would be cut if the new government included politicians with a strong sectarian bias.
The Iraqi prime minister dismissed the US warning.
Ibrahim Jaafari said he did not want a sectarian government, but would not accept interference in what was an "internal Iraqi affair".
"We do not need anybody to remind us, thank you."