Iraqi special forces have moved more than 1,000 people out of villages near the frontlines of the battle to retake the Islamic State of Iraq and the Levant-held city of Mosul and surrounding areas, where the UN says fighters have committed a number of abuses in recent days, officials said on Wednesday.
Haider Fadhil, special forces major-general, said residents of Tob Zawa and other villages were taken to a camp in the nearby Khazer region for their safety.
The International Organization for Migration says around 9,000 people have been displaced since the operation to retake Mosul began on October 17.
Al Jazeera's Hoda Abdel-Hamid, reporting from Erbil, said: "Up to one million civilians, if not more, are believed to be stuck inside Mosul. Ensuring their safety is as much of a challenge as defeating ISIL."
READ MORE: Can Mosul survive ISIL?
ISIL, also known as ISIS, took control of the city in 2014. Mosul is now the group's last major urban bastion in Iraq.
The special forces were undertaking cleanup operations in areas retaken from the fighters to the east of the city, where troops uncovered a vast tunnel network used by ISIL to shuttle fighters and supplies by motorcycle, Major Salam al-Obeidi said.
To the south of Mosul, another Iraqi commander said ISIL has been withdrawing from the town of Shura toward the city, taking civilians with them to use as human shields and leaving behind explosive booby-traps to slow the troops' advance.
"These small villages are secondary to them, Mosul is much more important," said Brigadier-General Alaa Mehsin, of the Iraqi army's 15th Division. "They don't want to waste their energy." He said a small number of fighters and civilians were still inside the town.
Also on Wednesday, the Kurdish Peshmerga took control of villages west of Bashiqa - a key town north of Mosul - after two days of clashes with ISIL.
Peshmerga General Bahram Yassin said ISIL was using car bombs, explosives and tunnels, as well as drones equipped with small bombs, to strike his troops' positions.
Meanwhile, sources told Al Jazeera that seven ISIL fighters and three civilians were killed in a US air strike north of Mosul.
Iraqi forces have been pushing toward Mosul from several directions since the launch of the widescale offensive, which involves more than 25,000 Iraqi soldiers, Kurdish forces, Sunni tribal fighters and state-sanctioned Shia militias. It is expected to take weeks, if not months, to drive ISIL out.
The fighters have had months to prepare for the long-awaited operation.
"They've really dug in, literally, and started putting up the berms, the trenches, the tunnelling systems," said a US military official, speaking on condition of anonymity. "And they're quite extensive tunnelling systems, some of them stretching upward of two kilometers [over a mile]."
He said Iraqi forces have found homes near Mosul where the lights are wired with explosives that detonate if you flip the switch. Inside Mosul, ISIL has set up large concrete barriers known as T-walls, blocking off several streets.
ISIL is also believed to have grown increasingly brutal as it seeks to eliminate any potential threats from among the local population, killing alleged spies as well as former members of the Iraqi security forces.
The UN High Commissioner for Human Rights said on Tuesday that ISIL appears to have carried out a number of abuses in recent days in and around Mosul, including killing 50 former Iraqi police officers they had been holding in a building near the city.
Spokesman Rupert Colville said Iraqi forces found the bodies of 70 civilians who had been shot dead in the Tuloul Nasser village, some 35 kilometres south of Mosul. He said it was not immediately clear who was responsible for the killings, and cautioned that it was hard to immediately verify the reports.
He told reporters in Geneva that the UN rights body also had reports that the fighters gunned down 15 villagers south of the city and threw their bodies in a river. In the same village, ISIL tied six people to vehicles by their hands and dragged them around because they were related to a tribal leader battling the fighters, he said.
"We very much fear that these will not be the last such reports we receive of such barbaric acts," Colville said.
Source: Al Jazeera News And Agencies