TWO children tragically died following an incident in the water off Bournemouth Pier on Wednesday afternoon.

A man has been arrested on suspicion of manslaughter as a police investigation remains ongoing into the circumstances surrounding what happened.

Here's everything we know about what happened. 

What happened?

The ambulance service was called to a "sea incident” in Bournemouth at 4.07pm on Wednesday.

Two people were pulled from the sea and taken to hospitals in Bournemouth and Poole with "critical injuries".

Tragically, a 17-year-old boy from Southampton and a 12-year-old girl from Buckinghamshire died, police have said. 

Floral tributes have since been left on the beach near the pier.

Daily Echo: Flowers left on Bournemouth beach

A further eight people were treated by paramedics following the incident.

They were treated by ambulance crews for non-life-threatening injuries.

What do we know about the children who died?

Dorset Police has said the two who died were not related to each other and those involved were “different people from different families” who were assisted by “great-spirited members of the public”.

What do we know about the arrest?

A man in his 40s, who was “on the water” at the time, has been arrested on suspicion of manslaughter.

Speaking at a press conference held outside the Bournemouth International Centre on Thursday, Dorset Police Assistant Chief Constable Rachel Farrell confirmed none of the swimmers had been in “physical contact” with a vessel and they had not jumped from the pier.

Daily Echo: The beach was cordoned off while emergency services dealt with the incident.

What have police said about jet skis and the pier?

The assistant chief constable said speculation jet skis had been involved was incorrect.

Police have also confirmed the youngsters who died had not jumped from Bournemouth Pier.

The assistant chief constable said: “As we have a person in custody, you will know there is only limited information I can give about the investigation.

“However, to avoid further speculation, I am able to tell you that it’s clear that yesterday a number of people already in the water got into difficulty and we are investigating the circumstances or event that caused that to happen.

“Early investigation indicates that there was no physical contact between a vessel and any of the swimmers at the time of the incident.

“I can also confirm there is no suggestion of people jumping from the pier or jet skis being involved.”

Daily Echo:

What more do we know about the investigation?

Members of the public have been urged not to speculate as police enquiries continue.

Ms Farrell said: “As you can imagine, we are at the early stages of our investigation, and we would ask people not to speculate about the circumstances surrounding the incident to both protect our inquiries and out of respect for the victims and their families.

“We are aware of a number of videos circulating on social media and we would urge people to refrain from doing this.

“We know the beach was very busy when the incident occurred. I am today urging anyone who saw what happened or has any information that may assist to please come forward.

“If anyone has relevant phone footage then they can contact Dorset Police through our major incident public portal where they can upload the images and we will share the links on social media.

“This operation is named Operation Marble. So please share the images with the police rather than on social media.”

Daily Echo: The press conference at the BICThe press conference at the BIC (Image: PA)

What has BCP Council said? 

Bournemouth, Christchurch and Poole Council leader Vikki Slade said the authority is working with the emergency services and will be assessing safety in the water near the pier.

“There are specific rules relating to the buoys in the water but there is no evidence that any of these rules have been breached,” she said.

Daily Echo: Air ambulances on Bournemouth beach on Wednesday afternoon

Which emergency services attended the incident?

South Western Ambulance NHS Foundation Trust (SWASFT) sent two air ambulances, six ambulances, one critical care car, two operations officers, a doctor, one hazardous area response team and a responding officer.

The coastguard helicopter, coastguard rescue teams and the RNLI also rushed to the scene. 

Dorset Police also attended to clear the beach to assist HM Coastguard and the ambulance service as they dealt with the incident.

Dorset and Wiltshire Fire and Rescue Service were also called to the scene with crews from Westbourne, Springbourne and Poole attending.

If I witnessed the incident, what can I do?

Dorset Police has asked anyone with information that could help their enquiries to come forward.

They should contact the force at www.dorset.police.uk or by calling 101, quoting occurrence number 55230083818.