A bomb exploded near a football field in Iraq on Thursday, killing five people and wounding at least 11, officials said.

The bombing in Madain, south of Baghdad, was just the latest in a string of attacks this year targeting young men playing Iraq's favourite sport.

Militants seeking to cause maximum casualties have also bombed other areas where crowds of people gather, including markets, parks, cafes, mosques and funeral tents.

Violence has reached a level unseen since 2008, and there are fears Iraq is slipping back toward the intense Sunni-Shiite bloodshed that peaked in 2006-2007 and killed tens of thousands.

With the latest violence, more than 50 people have been killed in attacks so far this month, and over 4,750 since the beginning of the year, according to AFP figures based on security and medical sources.