Islamic State’s leader Abu Bakr al-Baghdadi, who is reportedly hiding out in the besieged city of Mosul, released his first message since 2015, urging followers to wage all-out war and take the fighting into Saudi Arabia and Turkey. In the recorded message, the Islamic State (IS) chief expressed assurance that the militant group would ultimately be victorious in fending off the Iraqi forces and allies trying to retake Mosul, where he declared the ‘caliphate’ two years ago. The 31-minute-long recording, the authenticity of which could not be verified, was released by IS supporters on Thursday, according to Reuters. In the message, which does not specifically refer to Mosul, al-Baghdadi threatens non-believers with suicide attacks and ‘rivers of blood’. Al-Baghdadi, whose real name is Ibrahim al-Samarrai, said that the terror group’s militants will “unleash the fire of their anger” on Ankara, apparently referring to Turkish troops stationed at a base outside Mosul. The IS leader also threatened to execute multiple attacks in Saudi Arabia, targeting the Islamic kingdom’s security services, government officials and, notably, members of Al Saud royal family, while accusing them of siding with countries involved in hostilities in Iraq and Syria. As the troops advance on Islamic State’s stronghold, concerns about the safety of civilians have been rising. Russia’s Defense Ministry noted on Tuesday that the absence of escape routes for civilians may result in mass casualties as the battle continues.