A local MP has criticised Dorset Police for failing to properly communicate with the public about the circumstances that led to the death of two youngsters who got into difficulty in the water off Bournemouth beach.

Joe Abbess, a 17-year-old boy from Southampton, and Sunnah Khan, a 12-year-old girl from Buckinghamshire, were rescued from the sea during the incident on Wednesday, but both died later in hospital.

An inquest into both deaths is anticipated to be opened on Monday subject to confirmation by HM Coroner.

Conservative MP Tobias Ellwood expressed concern about a lack of clarity from local officers about the incident, which he said had led to “wild speculation on social media”.

“We do need to understand, learn lessons from this, provide clarity early on – just so people can have an assurance of mind as to what roughly happened,” he told BBC Radio 4’s Today programme.

The Bournemouth East MP said: “Certainly anybody would not want to impede or prejudice the investigation.

“But if the absence of any comprehensive statement becomes standard, I can see who, speaking on a wider picture and security level… those who wish us harm could leverage the void by misleading messaging.”

But David Sidwick, the Conservative Police and Crime Commissioner for Dorset, defended the police’s handling of the “complex” case.

Dorset Police have said that the beach was extremely busy at the time and they are continuing to appeal for witnesses to come forward.

Police have said that neither of the deceased young people or anyone else pulled from the sea at the time of the incident was involved in any collision or contact with any vessel in the water.

A man in his 40s, who was “on the water” at the time, was arrested on suspicion of manslaughter, and was released under investigation on Thursday.

Police have also said they are aware of “significant speculation” concerning a pleasure boat, which was in the area at the time of the tragedy off Bournemouth Pier.

The force has said the investigation is looking at all circumstances of the incident, including weather, wind conditions and the state of the water at the time.

Mr Sidwick, appearing on the Today programme, said that officers were working with a number of other agencies as they continue to try to work out what happened.

He said: “This is a complex investigation. It includes a number of agencies including the coroner’s office, the Marine Accident Investigation Branch, the Maritime and Coastguard Agency and the Dorset police.

“They are working together as fast as they can to find out what happened on that day. And I truly believe that they need to be given the time and space to do that fully, thoroughly, professionally and without hindrance.”

He suggested that while there would be a review of police communication “at the end of all this”, Dorset police had “moved to rule out those things which they could rule out when they had enough evidence to be able to do that”.

“What they can’t do is say what exactly happened and they shouldn’t because the veracity of any statement made by those investigating this incident must be beyond reproach,” Mr Sidwick added.

“And not just for any legal situation, but also because it is, to remind everyone – the victims and their families’ needs are paramount.”