Civilians in villages controlled by the Islamic State group in Fallujah, Iraq, can see the mortars and bullets flying in from the outskirts of the city. They know their liberators are beyond the tanks that sit just a few miles away, but they have no way of getting to them, or reaching safety. The Sunni militant group is preventing residents from leaving and Iraqi officials say they fear the extremists will commit crimes that amount to genocide.

“IS has been using civilians as human shields in Fallujah for more than three months, preventing them from leaving the city and confiscating the property of anyone who disobeys,” Iraq’s High Commissioner for Human Rights Fadel al-Gharawi said in a statement Tuesday. "Insurgents have planted improvised explosive devices in all of the city’s mosques and residential buildings and along the roads that lead to Fallujah."

Shiite volunteer groups, along with security forces in the national police, began attacking the Islamic State group, also known as ISIS or ISIL, in Fallujah, which borders Baghdad, earlier this month. ISIS has controlled large swaths of land in Fallujah for several months, but recently made a push to take over complete control of the city, which lies less than 50 miles from the capital.

So far, the Iraqi forces have managed to take back several smaller villages outside Fallujah, and are slowly moving toward the center of the city with the help of air cover from the Iraqi air force and the U.S.-led coalition.

If ISIS succeeded in capturing all of Fallujah, it would put Baghdad squarely in its crosshairs. Anticipating the Sunni militant group's advance, Shiite volunteer forces, also known as the Popular Mobilization Committee, launched an offensive in the area at the end of June.

The ISIS militants are dispersing themselves among the residents to avoid detection, Sunni sheikhs in the area said, making it difficult for the U.S. coalition to bomb them without also hitting civilians.

This video reportedly shows the destruction of the fighting in Fallujah and the conditions for civilians there:

The offensive in Fallujah comes as Sunni tribesmen and Iraqi security forces with the Defense Ministry prepare to take the city of Ramadi in the coming week. Ramadi is a strategic city in Iraq's Anbar province and is known in the country as the "Sunni heartland."

The Shiite militias, largely backed by Iran, are not going to take part in the Ramadi operation, but said in interviews with International Business Times on Tuesday that they, specifically the Badr Organization, would secure areas surrounding Fallujah and would prevent the Sunni militant group from gaining ground closer to the capital. They said they would continue to station themselves in Saqlawiyah and Fallujah.

The U.S. coalition has been dropping bombs on Fallujah and its surrounding area for months, fighters said, but the attacks have not succeeded in eliminating ISIS' presence because many of the Sunni sheikhs in the area are supporting the militant group with cash and weapons. Some have even pledged allegiance to the group.