WASHINGTON, March 6 (Reuters) - Multiple fast-attack vessels from the Iranian Revolutionary Guard Corps came close to a U.S. Navy ship in the Strait of Hormuz on Saturday, forcing it to change direction, a U.S. official told Reuters on Monday.

The official, speaking on the condition of anonymity, said the IRGCN boats came within 600 yards of the USNS Invincible, a tracking ship, and stopped. The Invincible was being accompanied by three ships from British Royal Navy and forced the formation to change course.

The official said attempts were made to communicate over radio, but there was no response and the interaction was "unsafe and unprofessional." (Reporting by Idrees Ali)

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