A crew member from the UK was among two workers killed in an attack on an oil tanker off Oman, the firm managing the vessel has said.

Zodiac Maritime said the incident, which it said was “suspected piracy”, had also resulted in the death of a crew member from Romania.

“We are not aware of harm to any other personnel. Our primary concern remains the safety and wellbeing of everyone on board and all those affected by the situation”, the company, which is based in the UK and owned by an Israeli family, said in a statement.

“Details of the incident are still being established and an investigation into the incident is currently underway. We continue to work closely with the UKMTO and other relevant authorities”.

The United Kingdom Maritime Trade Operations (UK MTO) – a part of the Ministry of Defence, which provides maritime security information – said it was a “non-piracy incident”.

It was not immediately clear how the Mercer Street tanker – a medium-sized, Japanese-owned tanker – was attacked or by whom.

The number of crew on board and their nationalities was also not immediately clear.

Iran has in the past been blamed for targeting tankers in the region with explosive devices – a threat that prompted the UK and its allies to send more warships to the Gulf to better protect the vital waterway.

The UK MTO said the vessel was about 152 nautical miles (280 km) northeast of the Omani port of Duqm when it was attacked on Thursday.

It gave no more details on the type of vessel, any cargo, to whom it belonged or about possible casualties.

Zodiac Maritime said in a statement: “We can confirm that there has been a suspected piracy incident onboard the product tanker M/T Mercer Street.

“The ship is a Japanese owned vessel managed by our UK based Zodiac Maritime Office. At the time of the incident, the vessel was in the northern Indian Ocean, travelling from Dar es Salaam to Fujairah with no cargo on board.

“We are in coordination and liaising with the UK MTO and other relevant authorities.”

A spokesperson for the Ministry of Defence said: “We are aware of reports of an attack on a merchant vessel off the coast of Oman. UK military headquarters in the region are currently conducting investigations.”

According to Eikon’s ship tracking, the Mercer Street was headed to Fujairah, a bunkering port and oil terminal in the United Arab Emirates, from Dar es Salaam, in Tanzania.

Iran and Israel have traded accusations over the past months of attacking each other’s vessels.