( CNN ) -- At least six people were killed in bombings across the Iraqi capital , Baghdad , on Thursday , police said . Four car bombs and two roadside devices exploded in five different areas around the city . Almost all of the neighborhoods were largely Shiite . At least 21 other people were wounded , police said . The blasts came one day after deadly attacks across the country that killed 47 people and wounded more than 120 others . Political and sectarian violence has raged in the past year . There has been constant tension between Sunnis and Shiites . Many Sunnis in Iraq have felt marginalized by the largely Shiite government . The Shiites have emerged politically in the country since Iraqi leader Saddam Hussein was overthrown in 2003 . It is n't yet known who is responsible for the Thursday violence . Anbar , other regions hit badly . The United Nations said 2013 was the deadliest year in Iraq since 2008 , with almost 8,000 people killed , most of them civilians . The figures remained grim in January . According to the U.N. mission in Iraq , more than 600 civilians and more than 100 members of the country 's security forces have been killed . The U.N. tally does not include those killed in a fresh wave of violence in Iraq 's Anbar province , west of Baghdad , where al Qaeda-backed militants and Iraqi security forces have been fighting since the end of last year . U.N.officials estimate that as many as 45,000 families have been displaced in Anbar . `` The U.N. continues to provide aid to those affected by the fighting in Anbar , despite the challenges posed by the deteriorating security environment and ongoing operations in the province , '' said Nickolay Mladenov , U.N. point man in Iraq . The ongoing violence in the Sunni provinces of Anbar , Salaheddin and Nineveh has raised concerns among some observers that parliamentary elections scheduled for April 30 will be delayed . `` The U.N. continues to hold discussions with senior political figures in an attempt to assist in paving the ground for a political solution to the crisis , calling on all to show national unity and address the root causes of violence in Iraq , '' Mladenov said . Human Rights Watch , the human rights watchdog group , issued a report Thursday on the detention of thousands of Iraqi women subject to torture and `` ill-treatment , including the threat of sexual abuse . '' The group cited the country 's `` weak judiciary '' and substandard trial proceedings as causes of the problem .
Shiite neighborhoods affected by violence . More than 100 hurt in the bombings . The latest wave of violence occurred amid longstanding instability .