The Stena Impero may have mistakenly sailed into Iranian waters due to “spoof” GPS signals, unconfirmed reports in the UK media suggest.

Spoofing is the process involving a GPS being made to display false information deliberately without the knowledge of the user.

Various UK media outlets, quoting unnamed sources, say GCHQ and MI6 are investigating whether Iranian intelligence transmitted spoof signals to the skipper of the UK-flagged tanker.