The US military has carried out about 10 airstrikes against ISIL in Libya's seaside town of Sirte over the weekend.

The Pentagon says Libyan forces are close to wiping ISIL out entirely. Those troops are moving in on the former extremist stronghold. But they are discovering gruesome remnants that provide a window into the world of ISIL operations.

Once home to seventy-thousand Libyans, Sirte is a ghost town now populated by patrolling Libyan militia and ISIL operatives.

"We see the ISIS operatives walking through our binoculars. They crossed the street so we informed the tank operators, they fired on them and Allah Uakbar - the target was hit," said one Libyan fighter, Sirte, Libya.

ISIL remnants: Tools used in public executions, hallmark forced “taxation” stamps, a “Libyan ISIL” emblem, basement prisons.

Isolated and tortured, prisoners scrawled desperate messages.

U.S. strikes have helped push ISIL into isolation. But the dividing line between fighters and extremists is tenuous.

Beyond this blockade, ISIL is in control.