COPENHAGEN, Feb 19 (Reuters) – On Thursday, Denmark's maritime authority announced that it has detained an Iran-flagged container ship in its waters because it was not properly registered.

The vessel, named "Nora", was previously sailing under a Comoros flag. However, Comoros informed Denmark that the ship was not listed in its registry, according to an email from the Danish authority to Reuters.

The Danish authority stated, "The ship is held until a flag state can prove to us that it is registered and fully certified." They also mentioned that a port state inspection would be carried out before the ship could be released.

They added that the inspection will take place when weather conditions are safe.

LSEG data indicates that the "Nora" is currently under the Iranian flag.

Danish broadcaster TV2, which was the first to report the news, stated that the vessel switched its flag from Comoros to Iran on Wednesday. However, Reuters could not independently verify the timing of this change.

The "Nora" shares the same International Maritime Organisation (IMO) number as a vessel previously known as CERUS. This container ship is on the U.S. Treasury's sanctions list, according to LSEG data.

IMO numbers are unique identifiers for vessels that do not change, regardless of name or flag changes.

According to LSEG data, the CERUS is listed under the U.S. Office of Foreign Assets Control (OFAC) Iran sanctions program and is associated with Argun Shipping Inc. and Reel Shipping LLC.

As of now, Reuters has been unable to contact Argun or Reel Shipping for comments.

TV2 reported that the vessel has been inactive for the past 25 days.