Iraqi security forces hold defensive line in Mosul

The Iraqi government has issued instructions to residents of Mosul on how to stay safe as forces prepare for an assault on the city which has been held by militants from the so-called Islamic state since 2014.

The BBC's Jonathan Beale reports as soldiers try to retake the al-Nuri Mosque, where IS leader Abu Bakr al-Baghdadi first appeared after the declaration of the caliphate.