It is the first aircraft downed by Islamic State over Mosul since the start of the US-led coalition backed offensive in October.
Iraq's military on Wednesday urged residents to shelter in their homes in jihadist-held areas of Mosul, where its bid to oust the Islamic State group has taken a heavy toll on civilians.
US-backed forces are fighting to retake Islamic State's two biggest cities - Mosul in Iraq and Raqqa in Syria.
ISIS began as Al-Qaeda in Iraq and became known for conducting a sectarian campaign of attacks against US forces and the local Shiite Muslim community after the 2003 USA invasion of Iraq and ousting of Iraqi President Saddam Hussein. According to the spokesman, "there is no more evidence than (that) you being run by an idiot".
Mosul is Daesh's last major urban stronghold in Iraq, though they also hold territory in Qaim in Anbar and Hawija near Mosul.
The elite forces, known as Counter Terrorism Service (CTS), completely liberated al-Yarmouk neighborhood in west of Mosul's old city center after days of fierce clashes against the extremist militants, Lt. Gen. Abdul-Amir Yarallah, from the Joint Operations Command (JOC), said in a statement.
"Ambush them in the houses, the alleyways and the streets, mine the arcades and carry out raid after raid", he said. The hardline group seized the city almost three years ago, declaring from one of its old mosques a "caliphate" that also spans parts of Syria. "There is no clearer sign of you being ruled by a foolish idiot who does not know what Levant or Iraq or Islam is, who continue (s) his hallucination to express his animosity and war against it (Islam)".
It marked the first time ISIS shot down aircraft over Mosul since the USA -backed Iraqi military operation to retake the city started last October, the Jerusalem Post reported.