Premier League club Cardiff City's record signing Emiliano Sala was reportedly on a light plane that disappeared over the English Channel on Monday night.
Police on the Channel island of Guernsey said the single engine Piper Malibu vanished from radar 24 kilometres north of the island at 8:23pm (7:23am AEDT).
The aircraft was carrying two people from Nantes in France to Cardiff in Wales, and the UK's ITV News reported French police confirmed Sala was one of those on board.
The 28-year-old Argentinian footballer signed for Cardiff City FC from FC Nantes for a little more than $27 million on January 19.
Air traffic control said the aircraft was flying at 5,000 feet but requested to descend as it passed Guernsey, before contact was lost it as it dropped to 2,300ft.
A large-scale sea and air search was immediately launched but called off several hours later due to strong winds and worsening sea conditions.
It was resumed at 8:00am on Tuesday morning but no traces of the aircraft have been found.
Cardiff City have not released a statement about the incident but told Sky News they were "seeking clarification" as to whether Sala was on the plane.
Yesterday Sala tweeted a farewell photo with his former FC Nantes teammates.
