Mystery still surrounds the deaths of two children in the sea off Bournemouth beach yesterday afternoon - with police arresting a man on suspicion of manslaughter.
A boy, aged 17, from Southampton, Hampshire, and a girl, 12, from High Wycombe, Buckinghamshire, were pronounced dead after being dragged from the water and airlifted to hospital.
Dorset Police have confirmed a man in his 40s was detained, but the circumstances of the tragedy remain unclear.
Emergency crews were called to the scene on North Beach at around 4.30pm, with a total of 10 people rescued from the water.
The area was evacuated and cordoned off as paramedics and lifeguards performed CPR.
However, investigators say those involved were not jumping from the pier and a vessel - including a jet ski - did not strike any of the victims.
Here's everything we know about how the tragedy unfolded:
Riptide warnings given to beachgoers
Beachgoer Stuart Clark, 42, said there were announcements throughout Wednesday afternoon telling people not to climb on the pier.
He said people appeared to take notice as no one was on there that he saw.
There was then another announcement at 4pm - around half an hour before the tragedy - about a "dangerous riptide in the water".
"It wasn't soon after that we saw a couple of swimmers in trouble out to sea," he added.
Swimmers get into trouble
10 people - all believed to be children - got into trouble in the water with RNLI life guards and members of the public rushing to their aid at just after 4.30pm on Wednesday.
The beach was evacuated and cordoned off as those involved were dragged from the water and initial CPR given.
The incident occurred near to the North Beach's Victorian pier, though police have denied anyone involved jumped from the structure.
They also said there is also no suggestion vessels, such as jet skis, were involved.
'Lifeless' victims floating
Ritta Saruchera, said her daughter and her friend were in the sea at the time and saw a teenage boy struggling, while another was "floating in the water".
Rob Creech said his son, 18, was swimming next to the pier and pulled the girl, 12, out of the water and onto the beach.
The dad said: "All of a sudden there were a lot of people on the pier shouting and screaming that there was somebody in the water. He swam to the other side of the pier and he found a young girl floating face down in the water.
"The emergency services were just arriving at the beach so he was shouting to them and scooped her up to swim to shore. He managed to get her out onto the beach and the emergency services took it from there."
Emergency crews scramble to scene
Police, fire and ambulance crews were dispatched to the scene at 4.32pm.
Two air ambulances landed on the beach and conveyed the two patients to hospital - while the others rescued were treated at the scene.
A spokesperson for the South Western Ambulance NHS Foundation Trust (SWASFT) had said six land ambulances were among the emergency crews sent out, with the children taken to Royal Bournemouth Hospital and Poole Hospital.
The Coastguard also confirmed yesterday afternoon that it was satisfied all people were accounted for.
Man arrested on suspicion of manslaughter
A man in his 40s was arrested by police on suspicion of manslaughter.
He remains in custody today.
His name and age or any details about what he was doing during the incident have not been made clear.
It is understood he is co-operating with investigators.
Police press briefing
During a lunchtime press briefing today, assistant chief constable Rachel Farrell confirmed there is "no suggestion" anyone was jumping from the pier.
She said she could only give a limited amount of information with the case active but said she was keen to avoid further speculation.
"It is 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," she continued.
"Early investigation indicates that there was no physical contact between a vessel and any other 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."
Issues with jet skis
There has been an ongoing issue between jetskiers and water users around the area of the pier.
There are yellow marker buoys 200m off the beach and water craft operating inside that area are restricted to speeds of 6 knots.
One local surfer said he witnessed three jetskiers 'buzzing the pier' close to the line on Tuesday, the day before the tragic incident.
Lawrence Hopgood said: "I was surfing the night before There were 3 jetskiers buzzing the pier and getting close to the line. A lifeguard went out on a jetski and spoke to them, then left.
"The jetskiers didn't leave but proceeded to do donuts near the surfers, whilst filming themselves."