The oil tanker attacked in the Persian Gulf by an Iranian gunboat Thursday is Liberian-owned, not American-owned, the New York-based company managing the ship said yesterday.

The 273,000-ton Peconic, hit by 18 small rockets, is owned by the Liberian company, Gray Shipping Inc., which is 100 percent owned by Liberian interests, a spokesman for Universe Tank Ships Inc. said.

"It's not a U.S. ship. It's a Liberian ship," spokesman William Crabtree said.

The Peconic was first reported to be an "American-owned" vessel flying under a Liberian flag, and the State Department also described it in this manner.

The attack attracted particular attention because even if the Peconic had been American-owned, the fact that it was flying a Liberian flag meant U.S. warships stationed in the gulf would not have been authorized to protect it.

Crabtree said the confusion probably arose because Universe Tank Ships is registered in Delaware and based in New York. Universe manages the ship for Gray, he said.

No Americans were among the crew, none of whom was injured, he said.

News agencies also incorrectly reported, he said, that the Peconic had been hit by "grenades." He said the projectiles were more like "small rockets" or "mortars," and that they had made one-foot holes in the side of the ship, all above the water line.