The fight for Mosul heated up Friday as Iraqi forces announced they had recaptured six districts in the eastern portion of the city occupied by ISIS militants. According to the military’s statement, government forces took back from ISIS the neighborhoods of Malayeen, Samah, Khadra, Karkukli, Quds, and Karama. According to multiple reports, Iraqi forces struck ISIS early in the morning, sending the militant group’s ambulatory units scrambling to extricate their wounded and dead from the battle. In return, militants were able to destroy a U.S.-made M1 Abrams tank being used by the government forces. One Iraqi soldier described to CNN the “crazy resistance” put up by ISIS fighters, with army convoys encountering heavy fire from suicide vehicle bombs, RPGs, and heavy machine guns. Anti-ISIS forces entered the city’s limits Tuesday for the first time in nearly two years and on Thursday the jihadis’ leader, Abu Bakr al-Baghdadi, released a message warning militants against any retreat, calling for “total war,” including the use of suicide explosions. Officials have warned that the battle to retake Mosul could end up being fought as a brutal “street to street” war. Mosul, with a population of 1.5 million, is the largest Iraqi city under ISIS control, and will likely become the scene of urban warfare as the U.S.-backed forces push further into the city’s center, and ISIS militants reportedly begin using citizens as human shields.