A Romanian oil company says Iranian forces have fired on and later boarded a Romanian oil rig moored in the Persian Gulf in an incident stemming from a commercial dispute.

A spokesman for the oil firm Grup Servicii Petroliere, GSP, in Bucharest says a worker telephoned from the Gulf Tuesday morning and said an Iranian military vessel had opened fire on the rig and that Iranian troops then boarded it.

The GSP spokesman said he had no information about any casualties, and said there has been no further contact with the rig. Iran has not commented.

The 13,000-ton Orizon rig, with 26 people on board, had been operating off the coast of Iran since last October.

Authorities say the Romanian firm is involved in a legal dispute with a Dubai-based competitor and the National Iranian Oil Company over use of the rig.

Reuters news agency quotes an official of the Dubai-based oil company as saying an Iranian court had earlier ordered that the mobile platform remain in Iranian waters.

Some information for this report was provided by AP and Reuters.