The bodies are believed to be the ones executed by the terrorist Islamic State (IS) militant group, the statement said, adding that forensics team will arrive to investigate the site. (AFP photo)

MOSUL, Iraq, Nov. 7 (Xinhua) -- The Iraqi forces found a mass grave containing the remains of some 100 decapitated bodies in the newly-freed town in south of the city of Mosul, a military statement said on Monday.

The troops found the mass grave at the compound of the Agriculture Collage on the western outskirts of the town of Hammam al-Alil, some 15 km south of Mosul, according to a statement issued by a military media office affiliated to the Iraqi Joint Operations Command (JOC).

The bodies are believed to be the ones executed by the terrorist Islamic State (IS) militant group, the statement said, adding that forensics team will arrive to investigate the site.

The Iraqi army and federal police entered the town of Hammam al-Alil on Saturday after heavy clashes with IS militants, and started later clearing operations in the town.

The discovery of the mass grave comes after three weeks of a massive offensive to dislodge the extremist militants from Mosul, their last major stronghold in Iraq.

On Oct. 17, Iraqi Prime Minister Haider al-Abadi announced the start of the offensive to retake Mosul, the country's second largest city.

Since then, the Iraqi security forces have inched to the eastern fringes of Mosul and made progress on other routes around the city, preparing for a major battle to storm the city and drive out IS militants.

Mosul, some 400 km north of the Iraqi capital of Baghdad, has been under IS control since June 2014, when Iraqi government forces abandoned their weapons and fled, enabling IS militants to take control of parts of Iraq's northern and western regions.