Mortar fire killed 11 people including four aid workers as civilians gathered to receive assistance in the city of Mosul, the UN said Thursday (December 22nd).

"According to initial reports, four aid workers and at least seven civilians queuing for emergency assistance in eastern Mosul city have been killed by indiscriminate mortar fire," Lise Grande, UN humanitarian coordinator in Iraq, said in a statement, according to AFP.

"Within the last 48 hours, there have been two separate incidents" that also wounded up to 40 people, Grande said.

"People waiting for aid are already vulnerable and need help. They should be protected, not attacked," she said, adding: "The killing of civilians and aid workers violates every humanitarian principle."

Meanwhile, Iraqi army and Counter-Terrorism Service forces are cautiously advancing on the neighbourhoods of Palestine, al-Nour and al-Wehda in east Mosul, the Ninawa Operations Command said Thursday.

"Special forces units on Thursday controlled six 'Islamic State of Iraq and the Levant' (ISIL) pockets, killed at least 20 ISIL terrorists and wounded many others" in the three neighbourhoods, Ninawa Operations Commander Nejim Eddin Karim al-Jubury told Diyaruna.

"The Mosul liberation operations are ongoing without any suspension, but we are just being more cautious as our troops reach densely-populated neighbourhoods where we cannot use greater force out of fear for the residents there," he said.

Additionally, Iraqi airstrikes killed at least 70 ISIL fighters in Ninawa province on Thursday, the Ministry of Defence said.

"The Iraqi air force targeted a gathering of ISIL terrorists south of Tal Abta area (west of Mosul), killing 20 prominent ISIL elements and 50 of their bodyguards," the ministry said in a statement.

In co-ordination with the 16th Division’s Intelligence Unit, the Military Intelligence Directorate seized an ISIL base containing 120-mm mortars and Katyusha rockets used in targeting security sectors, as well as military gear and CDs, in al-Shallalat area near the police academy, north of Mosul, the ministry said.

On the southern front, the directorate seized 45 pressure-operated fully-armed improvised explosive devices (IEDs) set to disrupt the advance of military forces, the ministry said.