A jack-up drilling rig owned by Borr Drilling sank off the coast of Mayumba in southwestern Gabon late on Saturday, October 24, 2026, leaving one worker dead and four others missing among the 115 people on board, according to three sources familiar with the matter.

The incident occurred at approximately 20:37 local time (19:37 GMT) in the Dussafu Marin permit area near BW Energy's MaBoMo production facility.

An Indian national, one of five people initially unaccounted for, was later found dead. The four remaining missing include three Gabonese nationals and one other expatriate. Of the 115 personnel on board, 110 were safely accounted for and are being brought ashore in Gabon, where care and support are being provided.

The Gabonese government has not independently confirmed the fatality, stating that five people remain missing and that search operations are ongoing. Borr Drilling's official updates have also continued to list five individuals as unaccounted for.

Cause: Punch-Through During Preload

Preliminary information from Borr Drilling indicates that the rig experienced a punch-through event during preload activities — one of its legs unexpectedly penetrated the seabed — causing a loss of stability and the subsequent sinking. The Prospector 5 had not yet begun drilling and was preparing for a planned campaign supporting BW Energy's operations.

Response and Investigation

Gabon's Ministry of Petroleum and Gas activated a crisis unit and ordered the navy to reinforce search and rescue operations at sea. The ministry also ordered a technical investigation, Petroleum and Gas Minister Clotaire Kondja said in a statement. The crisis unit brings together the ministry, the navy, state oil company Gabon Oil, BW Energy and Borr Drilling. Naval vessels and helicopters have been mobilised, with support from the neighbouring Republic of Congo, and authorities are preparing to deploy remotely operated underwater vehicles to inspect the sunken rig.

"We are deeply concerned for those who remain unaccounted for and everyone affected by this incident," said Borr Drilling Chief Executive Bruno Morand. "Our immediate priority is supporting the ongoing search and rescue efforts and the welfare of all personnel involved".

Production Halted, No Pollution Reported

BW Energy, which holds a 73.5% working interest in the Dussafu licence, said production at the MaBoMo facility had been shut down under standard procedures for drilling preparations. The company reported no damage to the facility or associated equipment and no accidental discharge of harmful substances into the sea. Gabonese authorities said no pollution had been observed in surrounding waters but were maintaining environmental surveillance near Mayumba National Park. Panoro Energy, which holds a 17.5% stake in the licence, also noted the production halt and absence of reported damage or discharges.

Rig and Contract Background

The Prospector 5, built in 2014, was under a contract secured in April 2026 for a minimum 320-day campaign, with options for another 220 days. It was preparing to drill four production wells at the Hibiscus and Hibiscus South fields under BW Energy's MaBoMo Phase 2 programme, which was expected to add up to 20,000 barrels per day of gross production at peak, with first oil targeted for the first quarter of 2027.

Search and rescue operations remain ongoing, and the full cause of the incident is subject to investigation.