Dubai: Pirates armed with guns and rocket propelled grenades shot a liquefied natural gas tanker off the coast of Oman on Wednesday, the International Maritime Bureau's anti-crime arm said.

"Pirates in a dhow armed with guns and RPG fired upon a LNG tanker under way. The dhow closed to 50 meters from the ship and fire shots of which three hit the vessel," according to the IMB piracy report.

It said the ship was not boarded by the pirates but did not say whether it was hit by any grenades.

Although relatively low-lying crude oil tankers have been targets of piracy and at least one has been hijacked, so far no high-sided LNG tankers are known to have been pirated.

The report does not say which tanker was involved but the incident took place on a route mainly sailed by Qatari LNG tankers taking fuel to Europe.