ISIS recently took control of areas near Ramadi, which is about 110 kilometers (about 70 miles) west of Baghdad and is the capital of Iraq's vast Anbar province, the country's Sunni heartland. The advance by the extremist group has forced thousands of civilians to flee east to Baghdad
But on Thursday, coalition airstrikes appeared to cut off ISIS' logistical resupply routes and prevent the group from advancing from its positions in the city, said Faleh Essawi, deputy chief of the Anbar provincial council.
CNN could not immediately confirm which country's planes conducted the airstrikes. However, the U.S. military has said the coalition carried out multiple airstrikes against ISIS targets near Ramadi in recent weeks.
Essawi told CNN earlier Thursday that the city's defenders still needed reinforcements and that they didn't have enough manpower or ammunition to continue holding their positions for long.
The offensive in Ramadi by ISIS, which took parts of Iraq
last year for what it says is its Islamic caliphate, shows its resilience despite months of U.S.-led airstrikes and its recent defeat by Iraqi forces in the northern city of Tikrit
Ramadi has seen intense and persistent fighting for months. ISIS took over parts of the city in the first half of last year, placing it at the heart of a deadly tug of war ever since.
Another member of the Anbar council, Aathal al-Fahdawi, said ISIS militants attacked government buildings in Ramadi on Wednesday night, but security forces and tribal fighters repelled the assailants.
Al-Fahdawi, like Essawi, said more troops and equipment are needed, arguing that the additional equipment that the city's defenders received Wednesday -- 15 Humvees -- was not enough.
The province's governor, Suhaib al-Rawi, also has pleaded for help. In a statement read on Iraq's state-run Iraqiya TV, al-Rawi called on multiple parties, including Iraq's central government, to send troops.
He called on the Hashd al-Shaabi militia -- a predominantly Shiite fighting group that worked with Iraqi troops and Sunni fighters to liberate Tikrit this month -- to help as well.
The recent fighting has driven a steady stream of refugees out of the city. On Wednesday, some residents packed what they could into metal carts as they prepared to flee on foot. People also were fleeing the areas where ISIS was advancing east of Ramadi.
At least 150,000 people have left, causing huge traffic jams on the roads leading outside the city, Essawi said.
Iraqi forces are facilitating civilian evacuations of the city, complicated by its density and narrow alleyways, defense officials said.
The Iraqi military pulled back its personnel to allow families to exit safely from the battleground, said Brig. Gen. Tahseen Ibrahim, head of the media office of Iraq's Ministry of Defense.
Now the military has regrouped its forces and has sent reinforcements to Ramadi, Ibrahim said.
That strategy was also used in Tikrit, supplemented by coalition airstrikes, the military spokesman added.
ISIS forces breached the northeastern part of Ramadi with the help of sleeper cells there, Ibrahim said.
The military planned to remove ISIS fighters from Ramadi soon, Ibrahim said.
Meanwhile, a U.S. military official, who spoke on the condition of anonymity, told CNN on Wednesday that the fall of Ramadi was "not imminent." Sizable parts of the city are under ISIS control or influence, but the area has been a target of a monthslong offensive, and Ramadi remains contested, the official said.