A man who disappeared at sea was reportedly stung by a jellyfish while swimming in the River Mersey.
Haydn Griffiths, from Wigan, was last seen at Derby Pool in New Brighton when he went swimming with a friend at around 10.30pm on Tuesday night.
Haydn, who should have been celebrating his 24th birthday on Friday, was trying to swim out to the wind turbines which line the coast when he disappeared beneath the water and failed to resurface.
The coastguard, police, lifeboat crews and fire service all joined a large search operation, which was eventually called off on Wednesday evening after 18 hours without success.
The Liverpool Echo reports that Megan Griffiths, Haydn's older sister, said she believes her brother was stung by a jellyfish and went into shock before his disappearance.
The Griffiths family travelled to Merseyside on Wednesday night to start searching miles of shoreline along New Brighton, Hoylake, Leasowe, Wallasey, Crosby and Widnes.
Megan described her "little bro" as "an athlete" and said she believes he is “out there and fighting”.
She said: "He got stung by a jellyfish, which Maria [who Haydn was swimming with] said he got sent into a shock and got cramp in both of his legs.
“Maybe he washed onto a remote beach and is too injured to find help.
"Maybe he’s still out at sea, hanging onto a buoy. Haydn is so strong. The RNLI coastguard have been incredible and the search party have been amazing.
“This is the most important search in the whole wide world as my incredible baby brother is out there. He is the strongest human I've ever met and I know he's out there fighting.”
Megan said the search for her brother is still going strong. In an update on Instagram, she said: "We have multiple drones out looking over marshland and places that can't be reached on foot, plus jet skis out on the mission too."
She went on to thank the emergency services and the dozens of people who came to the beach to search with them.
She said: "I just want to say how blessed our family is by the overwhelming support of friends, family and complete strangers. There are so many kind souls dedicating their time to search for Haydn.
"We will keep strong and keep searching."
Merseyside Police are continuing to carry out enquiries into Haydn’s disappearance. In a statement, officers issued a description and said he was last seen wearing dark coloured swimming shorts.
Haydn is white, 6ft 1in tall, of athletic build, with short blonde hair and blue eyes.
The force added: "We are continuing to carry out enquiries following reports that a 23-year-old man, Haydn Griffiths, has gone missing while swimming in the River Mersey off New Brighton at around 10.30pm on Tuesday.
“Haydn was last seen in the water at the Derby Pool, New Brighton, wearing dark coloured swimming shorts attempting to swim towards the windmills in the area.
“An extensive search of the river was carried out last night and today by the Maritime and Coastguard Agency but Haydn was not found and the search has now been suspended.
"Haydn is white, 6ft 1in tall, of athletic build with short blonde hair and blue eyes. Enquiries remain ongoing to find Haydn.
“If you see Haydn or have any information, please contact us via @MerPolCC on Twitter, 'Merseyside Police Contact Centre' on Facebook, 101, quoting reference 22000518807.”
