Baghdad (CNN) -- At least 12 people were killed and more than 50 wounded in car bomb attacks on two predominantly Shiite areas in Baghdad Monday, the Iraqi Interior Ministry said, the latest incidents in a wave of sectarian violence.
At least five died and 32 others were wounded when a parked car bomb detonated at a Shiite mosque in an area of southwestern Baghdad, the ministry said.
In addition, the ministry said, seven was killed and 19 others were wounded when a parked car bomb detonated at a market in the al-Shaab area of eastern Baghdad.
Earlier in the day, at least one Shiite pilgrim was killed and 10 others wounded in a bombing south of Baghdad, officials said.
An Interior Ministry official said a roadside bomb struck pilgrims in Mahmoudiya south of the capital on Monday morning as the pilgrims were on foot heading to the southern city of Karbala.
Hundreds of thousands of Shiites are making their way to Karbala to commemorate the Arbaeen pilgrimage this weekend.
Arbaeen is the pilgrimage marking the end of a 40 day mourning period for the death of Imam Hussain, the grandson of the Prophet Mohammed, a seventh century imam and one of Shiaa Islam's holiest figures.
Since 2003, attacks blamed on Sunni extremists have often targeted the pilgrims -- many of whom make a lengthy journey on foot to the Shiite holy city of Karbala.
Over recent days near daily attacks on pilgrims have left scores dead and wounded.
The official said a roadside bomb south of Hilla on Sunday wounded at least nine Afghan pilgrims.
The deadliest attack was on Thursday when a suicide bomber struck an army checkpoint west of the southern city of Nasiriya where pilgrims had gathered. The official said the death toll from that attack alone left at least 44 dead and more than 70 others wounded.
Bombings Thursday in Baghdad targeted the Shiite areas of Sadr City and Kadhimiya. The violence comes amid one of Iraq's worst political crises since 2003. A political deadlock has the government divided along sectarian lines and is raising fears, in the wake of the U.S. military's departure, of a return to the sectarian violence that gripped the country for years.
Officials say such attacks are aimed at reigniting the sectarian war.
Security on the routes used by the pilgrims has been heightened. Many roads have been closed to traffic and security at checkpoints was increased ahead of the pilgrimage.
In the predominantly Sunni city of Falluja, west of Baghdad, the homes of two policemen were destroyed in bomb attacks on Sunday evening, police in the city said.
At least five bombs were placed and detonated around the homes of an officer and a policeman in the area of Jbail south of Falluja. The houses were empty at the time.
Following the bombings, a vehicle ban was imposed on the city at 9 p.m. and lifted Monday at 5 a.m.
Police in Falluja say the bombings follow a bomb attack on an army checkpoint in the southern part of the city on Saturday that killed two soldiers and wounded another one.
In Baghdad on Monday, gunmen armed with pistols and silencers shot dead the head of a bank and her husband as they were leaving their home for work in the central Karrada district.
While violence has drastically dropped in recent years, shootings and bombings continue on a daily basis in Iraq.
The group Iraq Body Count, that has recorded Iraqi casualty figures since 2003, estimated in a report last week that more than 4,000 Iraqis were killed as a result of violence in 2011.
IBC reported almost the same death toll for 2010.
"There has now been no noticeable downward trend since mid-2009," IBC reported. "As observed in IBC's previous annual report, recent trends indicate a persistent low-level conflict in Iraq that will continue to kill civilians at a similar rate for years to come."