People are seen at a cafe where men, including fans of Spain's Real Madrid football club, had gathered, after an attack by gunmen in the predominately Shi'ite Muslim town of Balad, Iraq, May 13, 2016. [Photo/Agencies]

Football fans

The intelligence official said fighters from the powerful Iranian-backed Badr Organisation raided a nearby house and detained 13 members of a Sunni family. There were reports of gunfire in an adjacent orchard.

Iraqi authorities are facing scrutiny over security breaches that allowed suicide attackers to set off three bombs on Wednesday in Baghdad, killing at least 80 people.

The country is also struggling through a political crisis over a cabinet overhaul that has crippled government for weeks and threatens to undermine the US-backed war against Islamic State, which still controls swathes of territory in the north and west it seized in 2014.

The fight against the ultra-hardline Sunni militants has exacerbated Iraq's sectarian conflict, mostly between the Sunni minority and the Shi'ite majority, that emerged after the US-led invasion in 2003.

A 22-year-old victim named Tahseen told a doctor he had been smoking a water pipe when a man wearing civilian clothes and a bandolier filled with ammunition crossed the street towards al-Furat Cafe. He recounted hearing several blasts, likely from stun bombs, amid gunfire that lasted about ten minutes.

Inside the cafe hung pictures of famous footballers and a sign for a local group of Real Madrid fans. Witnesses said there was no match on Thursday night but spectators often congregated there.

Real Madrid said its players would wear black arm bands on Saturday to honor the victims.

"Football and sport shall always be spaces in which to come together and in which harmony and peace reign and with which no form of barbaric terrorism will be able to compete," it said in an online statement.

A suicide bombing in March at a youth football match south of Baghdad killed 26 people and wounded 71 others.