Switzerland’s Advantage Tankers has expressed concern over the welfare of seafarers on the seized suezmax Advantage Sweet.

The 159,000-dwt ship (built 2012) was boarded by naval forces and taken to Iran on Thursday.

The move appeared to be a response to the US seizure of a Greek-controlled tanker carrying suspected Iranian crude.

The operator and manager said the ship was fully laden and was on passage from Kuwait to Houston, Texas, with 24 crew on board comprising 23 Indian nationals and a Russian.

An Advantage tankers spokesman added: “We remain very concerned for our crew and wish to see them repatriated as soon as possible.”

The Tugrul Tokgoz-led company understands the Advantage Sweet is being held at the port of Bandar Abbas in Iran.

“No contact has been had with the vessel since the boarding, but seafarers’ families are comforted by the fact that in similar hijacks, no harm has come to crew members being held,” the manager added.

Advantage considers the safety and welfare of the crew members its first priority.

The company is contacting the Indian and Russian governments, as well as embassies and maritime authorities, to give all its support to efforts to ensure that the crew members are released from detention and “can return to their homes and loved ones with all possible speed”, it said.

A dedicated call desk has been established by the company for families of those on board to hear any latest news of their loved ones and their well-being.

The vessel was carrying a cargo of Kuwaiti crude for US charterer Chevron.

Chevron said it is aware of the situation involving the Advantage Sweet.

The charterer told Reuters it is “in contact with the vessel operator with the hope of resolving this situation as soon as possible”.