Faced with a shrinking grip throughout the country, ISIS fighters are stepping up their assaults on Libyan forces by deploying lethal IEDs.
The terror group is also increasing the number of suicide attacks and snipers in a bid to hamper soldiers loyal to the UN-backed Government of National Accord (GNA) in Tripoli.
One doctor explained that ISIS fighters are trying to make sure those targets -- if they don't die -- at least will not be able to fight again.
"The snipers attack usually the spine here. They choose to fire at the spine because brain injury and heart injury if he survived, he's going to fight again," says Nabeel Aqoub, a doctor working in Sirte.
The ongoing offensive against ISIS will prove a litmus test for the new Tripoli government, which along with American air support, is fighting to bring prosperity to the post-Arab Spring state where President Barack Obama committed what he himself called the worst mistake of his presidency -- not preparing for the aftermath of former dictator Moammar Gadhafi's removal.
US Defense Secretary Ash Carter said fighters for the terror group are now trapped in Sirte.
"With the support of our air strikes those forces, those GNA-aligned forces have now cornered ISIL in one small section of the city of Sirte and I expect that they'll eliminate any remaining opposition shortly," Carter told reporters Wednesday, using another acronym for ISIS.
Why Sirte matters
Once home to Gadhafi, the sprawling Mediterranean city fell to extremists in the chaos that followed the 2011 revolution. That chaos created a vacuum that ISIS quickly took advantage of, flooding the city with foreign fighters in 2014 and regenerating it as the group's largest stronghold outside Iraq and Syria.
It became a key base of operations for the organization, a place from where it carried out the gruesome mass beheadings of Egyptian Coptic Christians in February 2015 and filmed it for the world to watch. And five months later launched an operation to kill 38 tourists on a sun-drenched beach in neighboring Tunisia.
In June, US officials estimated there were 4,000 to 6,000 ISIS militants in the country.
A battlefield in flux
The US bolstered the GNA by launching two months of airstrikes
in August -- a move intended to "deny ISIL a safe haven in Libya from which it could attack the United States and our allies," according to Pentagon spokesman Peter Cook.
But as the international community and Libyans worked to free Sirte, thousands of civilians abandoned their homes, leaving the city largely deserted.
Those who escaped shared tales of terror, describing public beheadings and a deteriorating humanitarian situation with little available food or medical care, according to a Human Rights Watch report
published in May.
Misrata, the city to the west of Sirte, took in those who fled the reign of terror and earlier this year began fighting an enemy they were woefully unprepared to defeat. But when the US began providing air support in August, the tide turned and ISIS's defenses were breached.
What lies ahead?
For the GNA, and Libya as a whole, there will be more testing trials. Gen. Khalifa Haftar, a renegade who opposes the rule of the US-backed Tripoli government, took control of the country's lucrative oil crescent
this week and directly threatened the authority of Prime Minister Fayez al-Sarraj.
"This development will further hinder oil exports, deprive Libya of its only source of income, and increase the division of the country," said Martin Kobler, the head of the UN Support Mission in Libya
"This has to stop. Libyan natural resources belong to all Libyans."
Now on the verge of victory in Sirte, those who chose to stay say they have grown tired of the perpetual wars and the toll it's taking. They want peace for the next generation.
"All of us, we hope to finish today before yesterday. We are tired from 2011, war after war. We lost a lot of people," says Waleed Mohammed, another doctor based in Sirte. "If the patient dies it's okay but the problem is the handicap. And most of them are teenagers. All of them young active people in our community."