Tripoli, Libya (CNN) -- Libyan troops are surrounding the city of Bani Walid, awaiting orders to enter what had been a stronghold for late dictator Moammar Gadhafi as those inside appeal to the international community for help.
Massoud al-Waer, a local official, told CNN late Friday that Bani Walid was under siege with no food or fuel able to get in, nor even fresh oxygen for its main hospital.
The standoff -- and possible military offensive -- stems from the death of a Libyan revolutionary fighter from Misrata credited with capturing Gadhafi last year.
Omran Shaaban and two other fighters were kidnapped near Bani Walid in July. He was released two months later, at which point he was in bad shape physically. After being transferred to a hospital France, Shaaban died September 24 of the aftereffects of gunshot wounds.
One day after his death, the country's General National Congress authorized the Libyan ministries of defense and interior to use force, if necessary, to arrest those responsible for allegedly kidnapping and torturing Shaaban.
The national assembly also called for the release of the others being detained in Bani Walid, giving those in the city 10 days to comply -- or else the North African nation's military would take action.
The deadline for that ultimatum was Friday.
And over the past week, Libyan army troops and militia members from different parts of the nation -- including Misrata -- mobilized and surrounded Bani Walid. Bani Walid and Misrata have a longstanding rivalry.
The chief of staff for Libya's army issued a statement Thursday calling on the people of Bani Walid to cooperate by handing over the wanted individuals to avoid a military assault.
Yet many in Bani Walid remained defiant Friday, turning out in large numbers to protest the national government's demands and call for the release of those from the city being held about 130 kilometers (80 miles) to the northeast in Misrata, according to al-Waer.
"They treat us as if Bani Walid is not part of Libya," the city official said.
Hundreds of Bani Walid residents have been arrested by armed militias, according to the human rights advocacy group Amnesty International. Many continue to be detained without being charged, or put in trial, across Libya, and have been tortured or otherwise ill-treated, Amnesty said.
Meanwhile, talks are ongoing to resolve the issue in Bani Walid, without the use of force, al-Waer added. But he said that many residents are "anticipating a military offensive, but will not leave the city and are ready to die in Bani Walid."
Bani Walid was a holdout of pro-Gadhafi loyalists until the very end of the fighting late last year. And tensions between residents and fighters aligned with what was the National Transitional Council -- and later the fledgling Libyan government -- continued to simmer after the city's fall.
A petition was being circulated Friday around the inland city, which is about 170 kilometers southeast of the capital, Tripoli, asked the U.N. Security Council to convene an emergency meeting and act "to immediately intervene to protect the civilians in the town."
The petitioners claimed that pro-government "armed militias" were trying to indiscriminately kill large numbers of people in Bani Walid, because of the city's history in support of Gadhafi. They report "bombing on civil neighborhoods" on October 1 "with no regards to the lives of unarmed civilians."
"The Libyan government claims that it is trying to arrest some criminals in the town. But the question is: Could those criminals be arrested with mortars, missiles and a ban on daily necessary requirements?"
Amnesty joined those calling for restraint Friday night. It issued a statement urging "Libyan authorities to avoid unnecessary and excessive use of force in the city and to ensure essential medical supplies are allowed into the city."