The footballer died when a small plane taking him from France to the UK crashed in the English Channel.
A 64-year-old man has been arrested over the death of Cardiff City footballer Emiliano Sala earlier this year.
Police said the man was from North Yorkshire and was detained on suspicion of manslaughter by an unlawful act.
The man has since been released while investigations continue.
Sala, 28, and pilot David Ibbotson, 59, were killed in a plane crash over the English Channel in January.
Detective Inspector Simon Huxter, of Dorset Police, said: "We have carried out a wide-ranging investigation into the circumstances of the death of Mr Sala and continue to work with partner agencies including the Civil Aviation Authority.
"As part of this investigation we have to consider whether there is any evidence of any suspected criminality.
"And as a result of our inquiries we have today, Wednesday June 19 2019, arrested a 64-year-old man from the North
Yorkshire area on suspicion of manslaughter by an unlawful act.
"He is assisting with our inquiries and has been released from custody under investigation."