"A powerful explosion, the causes of which have not yet been established, occurred this morning during a secret meeting of the commanders of the Daesh group… in central Mosul, the capital of the Nineveh province," the source told the Alsumaria broadcaster.
The source added that according to unconfirmed information, the explosion killed several commanders of the group, including the commander of the elite battalions of the Daesh, directly linked to the group's leader, Abu Bakr al-Baghdadi. The channel did not specify which party was behind the explosion.
Earlier in the day, the Iraqi government forces resumed the offensive on Mosul after a three-day pause.
Mosul, the second largest Iraqi city, is the main stronghold of Daesh in Iraq. The city was seized by Daesh, a jihadist group outlawed in Russia and many other countries, in 2014 along with a number of other northern and western Iraqi cities and towns.
On October 17, Iraqi Prime Minister Haider Abadi announced the start of the operation to retake Mosul from the Daesh, a jihadist group outlawed in Russia and a number of other states. More than 30,000 Iraqi and 4,000 Kurdish fighters are taking part in the offensive, backed by about 5,000 US troops and supported by coalition airstrikes.