Story highlights Iraqi Counter-Terrorism forces have cleared key government complexes in Mosul

Some of Mosul's bridges had already been damaged in US-led coalition airstrikes

Irbil, Iraq (CNN) ISIS has destroyed all five bridges crossing the Tigris River in Mosul, an attempt to slow the advance of Iraqi troops toward the western side of the city, according to Lt. Gen. Abdul Amir Rasheed Yarallah, the commander of Iraqi Forces in Nineveh province.

The bridges had already been damaged in airstrikes by the US-led coalition in recent weeks. In previous instances of ISIS taking out bridges ahead of Iraqi troop advances, including in the cases of military operations in Qayyara and Anbar, Iraqi forces built temporary or floating bridges, causing troops to slow down but not to stop.

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On Friday, Iraqi Counter-Terrorism Forces announced troops had reached Mosul's "Second Bridge," located on the east bank of the Tigris River, according to Iraq's Joint Operations Command. This follows a milestone earlier this week when Iraqi Counter-Terrorism forces reached the east bank of the Tigris River in Mosul for the first time since the kick-off of the large scale military operation to reclaim the city started on October 17, 2016.

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Iraqi Counter-Terrorism Forces have also cleared key government complexes as of Friday, including the new government complex in eastern Mosul as well as several Mosul University buildings in eastern Mosul -- which had at one time been a headquarters and killing ground for ISIS fighters.

The Tigris River divides eastern and western Mosul. Iraqi-led forces have not crossed into or started any anti-ISIS operations in western Mosul to date.