Iraqi troops reportedly entered the Islamic State-bastion of Mosul Thursday for the first time in two years as the leader of the extremist group urged militants under siege to obey orders and remain resilient in a new audio recording, according to a jihadist monitoring group.

CNN quotes Big Gen. Tahsin Ibahim, spokesman for the Iraqi ministry of defense, as saying units of the 9th Armored Division had entered the city, storming a neighborhood in the eastern part of the city.

The BBC, which has reporters embedded with the Iraqis, reports that elite Counter-Terrorism Service troops are facing fierce resistance after seizing control of the state TV building in Kukjali hours in the eastern district. Army units are also pushing into the south-eastern Judaydat al-Mufti area, according to the military, the BBC reports.

Although a 100,000-strong coalition, led by Iraq, has been advancing on the city, only Iraqi forces are entering Mosul, according to commanders, CNN reports. That reflects Prime Minister Haider al-Abadi's contention that the battle for Mosul is at its core an Iraqi fight, and that sectarian politics must be kept from the key battle.

As the military pressured increase on the Islamic State, the man purporting to be Abu Bakr al-Baghdadi also called on extremists to launch attacks in Turkey and Saudi Arabia in a message lasting more than 30 minutes that was released late Wednesday, the U.S.-based SITE Intelligence Group said.

“Oh you who seek martyrdom! Start your actions! Turn the night of the disbelievers into day. Totally decimate their territories, and make their blood flow like rivers!” he said in his first recording since the United States-backed offensive to retake Iraq's second largest city started more than two weeks ago.

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