A British rig worker has died in mysterious circumstances onboard the jack-up Seafox Burj operating offshore Qatar in the Persian Gulf region.

His co-worker at the offshore jack-up facility — also a British national — has been arrested by Qatari authorities on an allegation of battering his roommate to death and hospitalising a third worker after a violent row.

Qatari authorities have now opened an inquiry after the British worker was found dead on Monday at the offshore facility, local media reports have claimed.

All three offshore rig workers were contracted by UK-based subsea support company Film-Ocean, and the offshore jack-up was working for Qatar’s North Oil Company, Upstream understands.

A Film-Ocean spokesperson told leading Scottish news publication The Herald that the company “can regretfully confirm one person has been fatally wounded and another has been injured following a non-work related incident on an offshore installation off Qatar”.

The company noted that it is liaising with the Foreign, Commonwealth & Development Office, as well as with other stakeholders, to establish the full circumstances surrounding the incident.

An official from Qatar’s Ministry of Interior was quoted by local media as saying that law enforcement authorities are investigating the 12 December incident involving the three British nationals.

The dead man’s body was wrapped in a bed sheet and hidden in a bathroom on the offshore facility after he was allegedly hit by his co-worker, reports said.

Seafox and Film-Ocean have yet to respond to independent inquiries by Upstream.

Seafox Burj is a three-legged, self-elevating jack-up unit for accommodation and offshore support services.

The vessel was built in Mississippi in the US in 1972 by Marathon LeTourneau as an 82-C design jack-up drilling rig, and later converted in 2012 by Lamprell at its United Arab Emirates’ yard.