Daesh militants have threatened to kill residents in Ramadi, Iraq, if they raise a white flag as Iraqi military reinforcements surround the city for an anticipated assault, an Iraqi official said Wednesday.

Rajia Barakat, a member of the Anbar Council, told IraqiNews.com the extremist group is prohibiting civilians from leaving the capital of western Iraq's Anbar province.

"The ISIS threatened the people of Ramadi of death in the event of raising white flags and heading to the security forces," he said. "The people of Ramadi are living in a state of fear and panic after being threatened by criminal and terrorist gangs.

"The organization is besieging hundreds of families inside Ramadi."

The threats were made as Iraqi military forces made preparations to retake the city from Daesh, and several families attempted to evacuate the area.

The Iraqi military on Wednesday killed 13 IS militants after detonating 82 explosives in western Ramadi's Haditha district.

Maj. Gen. Ali Ibrahim Dbon, commander of al-Jazeera and al-Badiya Operations, told IraqiNews.com "the force also managed to blow up five booby-trapped vehicles and a Katyusha rocket base with seven missiles."

Maj. Gen. Ismail Mahlawi, commander of operations in Anbar, said reinforcement units, including "artillery batteries and tanks," arrived at his command Tuesday, adding "our last battle is storming the city of Ramadi, which will be launched in the next few days after the completion of all preparations."

A provincial security source confirmed the development, saying the reinforcements were gathering in the nearby town of Khaldiyah. The source said Iraqi military units were able to in recent weeks encircle Ramadi after multiple bloody battles with IS forces in surrounding towns.

Daesh fighters seized most of Ramadi in May, and while the Iraqi military, backed by U.S. air power and Iran-trained Shia militias, launched an offensive across Anbar province in mid July, gains have been limited.

Meanwhile, preliminary rocket and artillery barrages against Daesh positions in Ramadi and Khaldiyah Island, east of the city, killed dozens of Daesh fighters on Monday.

Dozens of people were killed Tuesday in northern, western and central Iraq during clashes between pro-government forces and IS militants, including in the Anbar province town of Garma, east of Fallujah.

U.S. Central Command on Tuesday said the U.S.-led coalition conducted 16 airstrikes against Daesh forces in Iraq the previous day, including one near Fallujah, seven near Sinjar, two near Tal Afar, four near Ramadi and two near Albu Hayat.

Dbon said on Tuesday 65 Daesh fighters had been killed during operations in the Albu Hyat area of Anbar province, while five vehicles used by the militants were destroyed and 75 explosive devices dismantled.

By Danielle Haynes and Fred Lambert

Editor's note: This article has been edited from the source material