A French energy company is facing war crimes allegations, which it denies, over a massacre near its multi-billon dollar international gas project in northern Mozambique in 2021.

In a complaint filed with French prosecutors, a human rights group accused TotalEnergies of complicity in war crimes, including the torture and execution of dozens of civilians held by local security forces in a cluster of shipping containers at its facility.

Total has always denied responsibility for the actions of government troops and related security forces who were involved in guarding the Afungi peninsula gas refinery development.

It was the biggest foreign investment project in Africa at the time.

The complaint was filed by the European Center for Constitutional and Human Rights (ECCHR), a human rights group.

Companies and their executives are not neutral actors when they operate in conflict zones. If they enable or fuel crimes, they might be complicit and should be held accountable, said Clara Gonzales, the ECCHR's co-programme director for business and human rights.

The massacre by Mozambican forces took place in resource-rich Cabo Delgado province, where government troops were battling violent Islamist militants, linked to the Islamic State group, with a gruesome reputation for beheading victims.

In March 2021, Islamists attacked the besieged town of Palma, where they killed or kidnapped 1,563 civilians living next to TotalEnergies gas plant on Mozambique's remote northern Afungi peninsula, according to Alex Perry.

The investigative journalist first documented the Palma death toll, and the subsequent reprisal massacre at the entrance to Total's compound, for Politico in 2024.

Perry called it the bloodiest disaster in oil and gas history.

Locals who sought help from the forces at the Total facility were accused of aiding the insurgents. Men were separated from the group by force and held in shipping containers. The exact number of civilians subsequently killed by Mozambican forces providing security for Total is not clear. Perry identified 97 victims but estimates the true figure could be double that.

Most people have never heard about any of this, in part because Total has acknowledged none of it. Today is a victory for truth, and accountability, Perry told the BBC.

The BBC has contacted TotalEnergies for comment.

The British government initially offered financial guarantees for UK companies seeking to take part in what was heralded as an unprecedented opportunity for economic development in Mozambique.

But after suspending support following the bloodshed in Palma, Britain is now being urged to walk away by environmental campaigners, who say the gravity of the allegations against Total must be a red line for the financial backers of its liquefied natural gas (LNG) project in Mozambique.

Total continued to demonstrate that it has learned nothing from the past: it just announced the lifting of the force majeure on its gas project, despite the dramatic security and humanitarian situation, Lorette Philippot from Friends of the Earth France said.

The UK and Dutch governments must refuse to renew their financial support and withdraw from Mozambique LNG, she added, like French banks Société Générale and Crédit Agricole.

Supporters of TotalEnergies' determination to proceed with the vast project in Cabo Delgado say it is a bold investment that could bring huge rewards to a neglected region of Africa.

But critics say it is an environmental, ethical and financial disaster. They draw links between Total's actions and struggles and those of another giant French company, Lafarge, which went on trial in France this month, along with eight former employees, over allegations that it paid jihadist groups in Syria to keep a cement plant there in operation.