Iraqi security forces have launched an investigation into the deaths of 20 civilians during an operation to capture two terrorist suspects on Thursday.
The tragedy occurred in Rashayed village in the central province of Babylon, just south of Baghdad, when special forces and intelligence officers prepared to raid the home of one of the suspects, a security source told AFP.
Security forces "pursued two individuals accused of terrorism", a security force statement said.
"After surrounding him he opened fire indiscriminately at the forces."
State news agency INA reported that the mission was taken to arrest "wanted people hiding in a house, the owner of which opened fire on the security forces".
"Upon entering the house when the owner refused to surrender, the unit found that all members of his family, numbering 20 civilians, had died," the agency reported.
An intelligence source told AFP that the suspect was a member of ISIS.
Iraq proclaimed victory against ISIS in late 2017 after reclaiming parts of northern and western regions seized by the extremist group in 2014.
A low-level ISIS insurgency, particularly in the north, continues to disrupt efforts to restore stability to Iraq, which is scarred by years of warfare and unrest.