Islamic State group leader rallies his fighters in Mosul

IRBIL -- The shadowy leader of ISIS has released a new message urging his followers to keep up the fight for Mosul as they defend the city against a major offensive aimed at routing the militants from their last urban stronghold in Iraq.

Abu Bakr al-Baghdadi's rallying cry came in a sermon-like recording, more than half an hour long, distributed by the militant group's al-Furqan media arm late on Wednesday. It was not clear when the recording was produced. Al-Baghdadi's whereabouts are unknown.

In his recording, al-Baghdadi rallies his fighters -- especially in Mosul -- and calls on them to obey orders while remaining resilient and steadfast.

"Oh you who seek martyrdom! Start your actions! Turn the night of the disbelievers into day," he says, according to a translation provided by the SITE Intelligence Group, a U.S. organization that monitors militant activity online, which reported the al-Baghdadi recording first.

"Totally decimate their territories, and make their blood flow like rivers," al-Baghdadi also says.