Finnish police have confirmed that they are to investigate the boating accident that claimed the life of a friend of JJ Lehto last week - and left the ex-F1 star himself requiring surgery in hospital for head injuries and broken ribs - revealing that 'some kind of offence is suspected'.

Lehto survived the impact - that occurred when the six-metre Searay 210 Fission speedboat in which he and his friend were travelling, and which belonged to him, hit a road bridge support at around 4am last Friday morning - by swimming ashore to summon help.

However, after an eyewitness who initially treated Lehto at the scene described him as drunk, it has been reported by Finnish newspaper Turun Sanomat that the former Benetton, Sauber, Scuderia Italia and Onyx ace subsequently failed a police alcohol breath test.

There is also speculation that the 300bhp boat was travelling significantly over the speed limit in the narrow stretch of water at Jomalvik, Raseborg, west of the capital Helsinki and on the country's southern coast - leaving the 44-year-old racer-turned-TV commentator potentially facing charges on the grounds of safety, dependent upon who was at the helm when the accident occurred.

"Some kind of offence is suspected, but I am not taking a position until it becomes clearer who did what," Inspector Juha-Pekka Vuorinen - leading the investigation - told Ilta-Sanomat, adding in an interview with HBL: "We cannot interview someone who is still strongly medicated. The doctors say he could be discharged [from hospital] in a week, and then we will hear from him as soon as possible."

An average of 55 people are killed every year in Finland in boating accidents, with alcohol intoxication and an unwillingness to wear life-jackets the principal culprits.