Cardiff City soccer player Emiliano Sala was on board a light aircraft that lost radar contact over the English channel late on Monday, French police sources said.
British and French coastguards scoured the seas off Guernsey on Tuesday for the single-engine plane after it went missing on its way from Nantes in western France to the Welsh city of Cardiff.
The 28-year-old Argentine forward joined Premier League strugglers Cardiff City from FC Nantes last week for a club record fee of around 17 million euros ($19.32 million). He had played in France since 2012.
Local coastguards were alerted by air traffic control at 20:23 GMT that an aircraft with two people on board had gone missing. Lifeboats and helicopters were sent out but the search was suspended four hours later as weather conditions worsened.
Search teams resumed work on Tuesday morning.
"At this time no trace of the missing aircraft had been found," Guernsey police said.
FC Nantes and Cardiff city officials did not immediately comment.
Sala had scored 12 league goals in 19 appearances for Nantes in France's Ligue 1 this season before switching this week to Cardiff.
