Iraqi troops who briefly seized a Mosul hospital believed to be used as an Islamic State base were forced to withdraw from the site, but managed to establish a base for army tanks nearby after days of fierce back-and-forth fighting, residents said.

The rapid advance into the Wahda neighborhood where the hospital is located marked a change of tactic after a month of fighting in east Mosul in which the army has sought to capture and clear neighborhoods block by block.

The ferocity of the fighting reflects the importance of the army's push from southeast Mosul towards the center, their deepest advance in a grueling seven-week offensive to crush Islamic State in Iraq's largest northern city.