Iraqi pro-government forces hold an Islamic State (IS) group flag in the Officers neighbourhood of Fallujah as they try to clear the city of IS fighters still holed up in the former jihadi bastion on June 19, 2016. Despite facing less resistance than expected from IS in Fallujah, an emblematic jihadist stronghold, sniper fire, car bombs and booby traps remained a risk for Iraq's forces as they try to clear central Fallujah of pockets of IS fighters. / AFP PHOTO / HAIDAR MOHAMMED ALI

A senior Iraqi military commander says about 2,500 Islamic State militants have been killed during a month-long offensive to recapture the city of Fallujah.

The counterterrorism forces’ chief in the operation, Lt. General Abdul-Wahab al-Saadi, told the local al-Sumaria TV late on Monday that the number of ISIS fighters inside Fallujah ranged between 3,500 to 4,000 when the offensive began in late May.

Iraqi troops have not disclosed their losses in Fallujah though the ISIS group claims to have killed dozens

Al-Saadi offered no specifics to back up the figure of 2,500 killed ISIS fighters. He claimed about 15 percent of them were foreign fighters.

He cited Iraqi police reports as saying 1,086 ISIS-linked suspects have been arrested. He didn’t say how many ISIS militants remain in Fallujah.