French energy company Total has shut its operations and withdrawn all staff from a site in northern Mozambique, following last week's deadly terror attack in the area, security sources said on Friday.
"Total has gone," a security source in Maputo told AFP, adding that "it will be hard to persuade them to return" this year.
A military source said: "All the facilities are abandoned.
"Total made a decision to evacuate all of its staff" after drone surveillance showed insurgents were in areas "very close" to the gas plant in Afungi.
Another source confirmed there were reports that extremists were not far from the site.
Afungi peninsula is only 10 kilometres from the town of Palma, which came under attack more than a week ago, resulting in the deaths of dozens of people, including at least two expatriate workers.
The brazen assault on March 24 was the latest in a string of more than 830 organised raids by extremists over the past three years, during which more than 2,600 people have died.
Total had already removed some staff and suspended construction work in late December following a series of violent attacks near its compound.
But last week's raid is seen as the biggest escalation of the insurgency ravaging Cabo Delgado province since 2017.
Many civilian survivors fled their homes, flocking towards the heavily secured gas plant.
An estimated 15,000 people have gathered near the site, while more are still arriving and "security is compromised", said another source.
The humanitarian "situation continues to deteriorate," added the source
Total's departure came as Afungi army commander Chongo Vidigal declared on Thursday the gas project was "protected".
"We are currently in the special area in Afungi and never had a terrorism threat," he said.
Total did not immediately respond to requests for comment.
Most communications were cut after the Palma onslaught began.
Thousands of troops have been deployed to Cabo Delgado, but Mozambique's ability to fight the insurgency has long been questioned, with analysts pointing to poor training and lack of equipment.
Government security forces are bolstered by a South African private military company, Dyck Advisory Group.
Total and its partners planned to invest $20 billion in the project, the largest amount ever for a project in Africa.
In February, Total chief executive Patrick Pouyanne insisted that the project, which the company inherited from US energy firm Anadarko, was still on track to begin operations in 2024.
He said this having reached agreement with Mozambican President Filipe Nyusi to set up a 25-kilometre radius secure zone around the site.
But last week, the extremists attacked, reportedly beheading residents and ransacking buildings in the latest rampage.
Hundreds, including many foreign workers, have been evacuated by air and sea, while thousands of locals walked to safety.
The UN said it has recorded at least 9,100 people internally displaced by the latest violence.
The violence has uprooted about 700,000 people from their homes since October 2017.
Extremists in Cabo Delgado have wreaked havoc across the northern province with the aim of establishing a caliphate.
The insurgents are affiliated to ISIS, which claimed responsibility for the Palma attack.