Tripoli, Libya (CNN) -- Loyalists to Libyan leader Moammar Gadhafi killed eight rebel fighters in a rare attack earlier this week in an opposition-held region near the Egyptian border, a medical official and an opposition spokesman told CNN Saturday.
The regime loyalists, riding in a convoy of nine vehicles, attacked an oil pumping station in the Libyan desert on Thursday, about 300 kilometers (186 miles) southwest of Tobruk, said Dr. Rida Benfayed, a physician who claimed he treated a rebel fighter injured in the attack.
Tobruk is a rebel stronghold one hour west of the Egyptian border and is the site of a key oil exporting facility where the rebels shipped out their first consignment of oil earlier this month.
Benfayed said the gunmen opened fire on a team of nine rebel military guards manning the pumping station. The regime loyalists set a tire on fire to burn the remains of a senior rebel guard, the doctor said.
The only guard who survived was shot twice in the leg but managed to escape and drive himself to Tobruk where he's in stable condition at a hospital.
Opposition spokesman Ahmed Bani confirmed the attack, which showed the regime's capability to strike deep into rebel territory with ambush-style attacks.
"He (Gadhafi) doesn't want us to sell the oil," Bani said. "This is a lesson for us. We will take measures to increase security along the pipelines."
Bani said the pumping station sustained damage in the attack, though the extent wasn't immediately clear.