"The remains were decomposed and showed signs of gunshot wounds to the skull," said Amar Nuri, an official in the western province of Anbar.
"They belonged to civilians probably executed by Daesh," he told the news website, using an Arabic acronym for the extremist group.
He did not say when the grave had been unearthed.
Ramadi, the capital city of Anbar, was recaptured from Islamic State in December 2015.
In recent months, Iraq has unearthed mass graves of people thought to have been killed by Islamic State in several areas of the country.
Last month, Iraqi Prime Minister Haider al-Abadi officially announced victory over Islamic State in Mosul, the group's last key stronghold in Iraq, after battling the hardline militia there for nearly nine months.
Islamic State still controls territory in Iraq, including areas south and west of Mosul.
"They belonged to civilians probably executed by Daesh," he told the news website, using an Arabic acronym for the extremist group.
He did not say when the grave had been unearthed.
Ramadi, the capital city of Anbar, was recaptured from Islamic State in December 2015.
In recent months, Iraq has unearthed mass graves of people thought to have been killed by Islamic State in several areas of the country.
Last month, Iraqi Prime Minister Haider al-Abadi officially announced victory over Islamic State in Mosul, the group's last key stronghold in Iraq, after battling the hardline militia there for nearly nine months.
Islamic State still controls territory in Iraq, including areas south and west of Mosul.