A seven-year-old girl who died after a bouncy castle she was playing in was blown away in Harlow has been named by police as Summer Grant, from Norwich.
A woman, 24, and a man, 27, have been arrested on suspicion of manslaughter by gross negligence, and bailed.
Paramedics were called to Harlow Town Park in Essex, just after 16:00 GMT on Saturday, where an event organised by Thurston fun fairs was taking place.
Summer was treated by ambulance crews but later died in hospital.
A post-mortem examination established the cause of her death as multiple injuries, Essex Police said in a statement.
It is believed the dome-shaped inflatable carrying Summer blew over a number of trailers and caravans in the park.
Ray Smith, a representative of the Showmen's Guild of Great Britain, said: "It was a sudden gust. Had it been a consistent wind they would have closed down all the inflatables."
The Kent and Essex Serious Crime Directorate is leading the investigation into the incident.
Det Insp Daniel Stoten urged people who had been at the event to contact police, and urged anyone who had video footage of the scene to get in touch.
He said: "This is a very tragic incident where a young girl has lost her life. My deepest sympathies go out to her family."
East of England Ambulance Service said the girl had suffered serious injuries when the inflatable was blown "some distance". She was treated by ambulance crews and the Essex and Herts Air Ambulance before being taken to the Princess Alexandra Hospital in Harlow.
A spokesman for the ambulance service said: "Our thoughts are with the friends and family involved on this sad day."
Floral tributes have been left at the gates of the park, where a section remains cordoned off by police.
Among them is an Easter basket, while a card on a bunch of flowers reads: "God has taken a beautiful girl for his angel. RIP Princess."
Almost £2,000 has been donated after an online fundraising drive for Summer's family.
On Sunday morning, police were still standing guard around the inflatable. BBC Essex reporter Nick Alliker said about 20 caravans and trailers and a couple of fairground rides remained in the park.
The Health and Safety Executive said it was assisting police with the investigation.
Last year a bouncy castle collapsed while children were playing on it during a fair in the park.
Harlow Council officers visited the site following the incident last May and suggested a number of health and safety improvements, including better stewarding of the event.
It was reported at the time that three children were treated by paramedics when the inflatable castle collapsed on them.
After news of Saturday's tragedy broke, Conservative MP for Harlow Robert Halfon tweeted: "My thoughts and heart go to family."
He said in a statement he would be asking for an "urgent inquiry" and to consider whether bouncy castles "should be banned from Harlow town fairs, until we can be sure that they are completely safe, so such a horrific tragedy never happens again".
Jon Clempner, leader of Harlow Council, said: "Harlow is a town in shock following this tragic incident yesterday. I can't imagine the heartache of the parents and family of the little girl who has died, and my thoughts are with them."