Islamic State jihadists in Mozambique killed dozens of civilians over the weekend during a violent seizure of Palma, a natural gas hub located on the country’s northeast coast that employs scores of foreign workers.

Hundreds of terrorists believed to be tied to the Islamic State (ISIS) stormed Palma on March 24, infiltrating military barracks, shops, and banks to begin a siege of the resort town. An ISIS propaganda outlet alleged on March 29 that 55 people, including Mozambican soldiers and foreign nationals, had been killed in the assault on Palma since last week, though this figure has not been independently verified. The Islamic State formally claimed responsibility for the attack on Palma through the same propaganda outlet on Monday, publishing a photo to the website allegedly showing a group of militants from its Mozambican branch in the town.

The militants attacked a convoy filled with unarmed civilians as it attempted to flee Palma’s besieged Amarula Hotel on March 26. “The defense and security forces registered the loss of seven lives of a group of citizens that left the Amarula hotel in a convoy that was ambushed by the terrorists,” Omar Saranga, a spokesperson for Mozambique’s defense department, told reporters on March 28, though witnesses say many more people are still unaccounted for.

“Hundreds of people fled the fighting, running into forests, mangroves or nearby villages,” the BBC reported on Sunday. “Some tried to escape the hotel in a convoy of vehicles on Friday, aiming for a nearby beach. At least 20 people were reportedly flown to safety in helicopters, but others were ambushed outside the hotel.”

“Witnesses have described hiding out while waiting to be rescued by boat, on a beach strewn with headless bodies,” according to the British broadcaster.

South African national Adrien Nel, 40, was among those killed as he attempted to escape from Amarula Hotel on Friday. Nel’s mother, Meryl Knox, told the BBC on Monday that he was riding in the fleeing convoy along with his father and brother as it was stopped by terrorists. The jihadis shot and killed Nel, but his father and brother survived the attack and recovered Nel’s body as they fled the ambush. Nel’s father, Gregory Knox, and brother, Wesley, “hid with his body in the bush until the following morning [March 27], when they were able to make it to safety in Pemba [155 miles south of Palma],” Mrs. Knox said told Reuters.

“No army to protect them, none of them having weapons, so it was a matter of run for your life or face these insurgents, who are so cruel and barbaric,” she told the BBC.

Dyck Advisory Group — a South African private security firm hired by the Mozambican government to defend Palma — told the BBC that the jihadists were “still in control of Palma” as of March 29.

“My guys are engaging these terrorists in skirmishes. The terrorists have taken cover in houses, which is what they always do. They come out and shoot at the aircraft, and they have hit and shot at our aircraft often,” the firm’s CEO, Lionel Dyck, told the broadcaster on Monday.

“Until we put sufficient troops in there to clear them out of the houses of Palma they will remain in control,” he added.

Dyck Advisory Group’s account of the current situation in Palma conflicted with Mozambique government statements on the town’s status on Monday. Mozambique’s state news agency quoted unnamed government sources on March 29 alleging Islamic State terrorists had been “driven out” of Palma and were “fleeing” towards the Tanzania border.