A CARGO plane has made a dramatic rapid descent into Glasgow Airport after declaring a mid-air emergency.

The Bluebird Nordic flight BF6810 was travelling from Billund in Denmark to Reykjavík in Iceland when it signalled the alert shortly beyond Shetland.

It declared the Squawk 7700 at around 7.30am before making a dramatic u-turn and descent towards mainland Scotland.

An emergency squawk is used to identify an aircraft that has a possible issue and enables it to have priority over other air traffic.

The exact detail of the emergency is not yet known, however Twitter user 'Flightradar24' wrote: "The reason is currently unknown but the descent to 8000 feet indicates a pressurization issue."

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A recording of the air traffic control communications posted online suggest there was "no hazardous cargo".

Asked why the flight did not land in the nearby Faroe Islands when it raised the alarm, Flightradar24 posted: "The runway at Faroe Islands is very short and not suitable for an emergency landing."

The flight departed from the Danish airport at 7.08am and was due to touchdown in Iceland at around 9am.

Flight radar app 'Plane Finder' shows it rapidly dropped to an altitude of around 8000ft by 8am, down from 31,000ft when raising the alarm.

The flight crossed over into mainland Scotland at around 8.15am.

It appears to have landed in Glasgow Airport shortly before 9am.

The plane regularly flies between Dublin and Reykjavík.

Bluebird Nordic and Glasgow Airport have been approached for comment.