By Stephen Stafford
BBC News
No criminal offences were committed in relation to the deaths of two people off Bournemouth beach, police said.
Sunnah Khan, 12, and Joe Abbess, 17, both drowned when they were suspected to have been caught in a riptide next to the pier at the resort on 31 May.
Police said they investigated whether a sightseeing boat, the Dorset Belle, had caused dangerous sea conditions but concluded it was not to blame.
A man, initially arrested on suspicion of manslaughter, will face no action.
A preliminary inquest hearing last month was told there was a “suggestion” a riptide led to the teenagers’ deaths.
Riptides are strong currents running out to sea that can quickly drag people and objects away from the shoreline to deeper water.
Det Ch Supt Neil Corrigan, of Dorset Police, said: “…information was given to police, which indicated that the movement of a boat – the Dorset Belle – immediately before the incident occurred could have contributed toward creating dangerous sea conditions.
“Witnesses suggested that there had been similar issues with the vessel having created such problems previously.”
The detective added: “…it was necessary to instruct an expert to review the material gathered by police. It was simply not possible to make a decision in this case without expert advice.
“The instructed expert needed time to review the evidential material and also to consider the prevailing tide and meteorological conditions at the time alongside the topography of the shoreline at the location.
“As a result of all of the evidence available, we are now able to confirm that we do not believe that the movement of the Dorset Belle contributed to the incident.”
Bournemouth, Christchurch and Poole Council suspended all boat operations from the pier “as a precaution” last month.
The beach had been packed during half-term when a number of people swimming off the eastern side of Bournemouth Pier got into difficulties shortly before 16:00 BST.
The area was cleared while emergency services dealt with the incident. Dorset Police said 11 people were rescued by RNLI lifeguards.
Joe and Sunnah both suffered critical injuries and died in hospital.
Joe, a trainee chef from Southampton was described as a “fabulous young man” by his family.
Sunnah’s mother Stephanie Williams, from High Wycombe, Buckinghamshire, paid tribute to her “beautiful daughter”, saying “no parent should ever have to go through what her dad and I are going through”.
Aylesbury MP Rob Butler raised the issue during a debate on water safety and drowning prevention.
Dorset Police said it would work with the coroner to provide a report covering the incident and investigation.
A further pre-inquest hearing is due to be held on 18 September.
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