The fresh violence came as US President George W. Bush assured Prime Minister Nuri al-Maliki that Washington had not set any deadline for the Iraqi government to get control of sectarian violence threatening to plunge Iraq into civil war.
US commanders have warned that Sunni insurgent groups such as al Qaeda battling the US-backed government would launch attacks during Ramazan. On Sunday, 10 people were killed in restive Kirkuk in multiple car bombs.
In the worst violence on Monday, two car bombs exploded in the religiously mixed area of Ur in northern Baghdad, killing 20 people and wounding 17, an Interior Ministry source said. One of the blasts went off near a market.
US and Iraqi forces have launched a security crackdown in Baghdad in a bid to ease violence gripping the capital, but bloodshed has continued largely unchecked.
South of the capital, at least 10 people were killed and 15 wounded when a car bomb went off near a bank in a market in the town of Suwayra, police said.
Two US soldiers were killed and two wounded after coming under fire in Kirkuk province, the US military said, adding to a death toll that could make October the deadliest month for US forces since January 2005.
Fifty-six US soldiers have been killed in Iraq this month.
Following a weekend rampage by black-clad militias that left at least 31 mostly Sunnis dead north of Baghdad, Sunnis were fleeing the town of Balad, a mostly Shia town surrounded by Sunni villages, officials said.
Adil al-Sumaidai, an official for the Sunni Islamic Party, told Reuters more than 60 families had fled their homes.
"There are families who do not know their destiny. This is sectarian displacement to stop Sunnis from living here."
The rampage was in apparent retaliation for the killing of 14 Shia labourers, whose bodies were found with their throats cut on Friday in an orchard in nearby Dhuluiya, a mostly Sunni town across the Tigris River.
BROTHER OF SADDAM PROSECUTOR SHOT
In Baghdad, a gunman shot dead the brother of the chief prosecutor in Saddam Hussein's trial for genocide against ethnic Kurds in his Baghdad home on Monday, prosecutor Munqith al- Faroon told Reuters.
Gunmen killed the brother-in-law of the chief judge in the trial and three defence lawyers have been killed in a separate trial against Saddam, prompting international legal groups to say violence between Saddam's fellow minority Sunnis and majority Shias makes a fair trial almost impossible.
Faroon said he did not know if the killing was related to his involvement in the trial, which resumes on Tuesday.
A US-backed court trying Saddam for the killing of Shia villagers in the 1980s could deliver a verdict on November 5, officials said, a ruling which could send the ousted leader to the gallows.
Amid growing sectarian bloodshed, Bush assured Maliki on Monday that the United States had not set any deadlines.
Maliki raised his concerns about a timeline, saying rumours could undercut confidence in the Iraqi government, during a 15-minute telephone call initiated by Bush, White House spokesman Tony Snow said.
"The president underscored his commitment to a democratically elected government of Iraq, encouraging the prime minister to ignore rumours that the United States government was seeking to impose a timeline on the Maliki government," Snow said.

Copyright Reuters, 2006