The family of a father-of-four who died on holiday in Benidorm say new evidence has further convinced them that foul play was involved in his death.
Nathan Osman, 30, from Pontypridd in South Wales, was on a long weekend break with friends in Benidorm in September 2024.
Less than 24 hours after he arrived, his body was found by an off-duty police officer at the bottom of a remote 650ft (200m) cliff on the outskirts of the resort.
He died from head and abdominal injuries after falling from height, a post-mortem found.
Local police said it was "a tragic accident" that occurred after Nathan left his friends in Benidorm to walk back to his hotel room alone.
But his family believe the investigation into his death has not been adequate, and that the local authorities have never considered the possibility of a homicide.
Their suspicions of foul play were first provoked by the fact that the remote location where Nathan was found was in the opposite direction to the hotel, and some distance away on foot.
They began doing their own investigating, building a timeline of events drawn from sources including CCTV, witness statements and Nathan's bank records, which they say showed attempts were made to use his bank cards the day after he died.
After presenting their findings to Spanish prosecutors as evidence that others may have been involved, the case was reopened earlier this year.
Now, the family have told Sarah-Jane Mee on The UK Tonight that new phone data they have uncovered suggests he couldn't have reached the spot he was found on foot.
After getting the phone back a couple of months ago, they say they tracked Nathan's last movements through a health app.
"There's a breakdown inside the app of every 10 minutes - the distance, pace, measurement of pace… every detail you can think of," Nathan's brother, Lee Evans, tells Mee.
"His pace wasn't consistent with a fast walk or even a sprint."
He said it was a faster journey, despite being uphill for 40 minutes, which has convinced the family that he was in a vehicle.
The family also went to visit the area where Nathan was found.
"We were a bit upset, but we were very pleased we went up there", his mother, Elizabeth, says. "We could see… there's no way he would have looked at that area and thought, 'I'm going up here.'
"You can see straight off, there's no clubs, there's no hotels up there, there's just the odd house dotted around. It was just out in the wild, there was nothing up there."
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The family says the phone data has helped them determine that he died around half an hour after he was seen on CCTV walking towards his hotel in the early hours of the morning.
"It was really ridiculous to think that my son would've walked up there [the remote location where he died] at 4am in the pitch dark."
After the family were interviewed by Mee in May, South Wales Police opened its own investigation into Nathan's death.
Lee says the Welsh force has been "appalled" by the lack of evidence turned over from the local police's investigation.
His and Nathan's father, Jonathan, says: "No procedures were followed. Nothing was cordoned off, it wasn't a crime scene. There's loads of things that could've been taken. Tyre tracks, foot tracks, nothing. No DNA taken."
Lee says: "All that we've done over the last year, this could've been squashed within the first week, two weeks [by local investigators].
"We've had to find out and keep delving into every possible outcome and overturn every stone possible. We started off with… a needle in a haystack, we had no direction or any support on which way to go."
What does Nathan's family hope for now?
Nathan's family say they have located 27 CCTV cameras which could have picked Nathan up in the area, after local investigators didn't find any.
Elizabeth says that after alerting Spanish police to the locations, they were told that the CCTV "wouldn't be working" or that footage would've already been erased.
"They just surmised everything," she adds.
But the family, who found the last known CCTV footage of Nathan earlier this year, are convinced there is still hope.
Lee says: "There's a number of CCTV footage in that area. We know there's a way of finding a vehicle of some sort."
But the family admit they may never find whoever could be responsible for Nathan's death because so much time has been lost.
Elizabeth concludes: "Nathan walks with us every day. We all believe that," adding that "all we want" is to find the ones responsible for his death and for him to "have the respect of a decent investigation".
Sky News contacted Spanish police, which declined to comment, adding the case is under judicial review and it doesn't want to hinder the course of the investigation.
South Wales Police told Sky News: "South Wales Police is carrying out enquiries on behalf of HM Coroner and a family liaison officer has been appointed to provide support."
(c) Sky News 2025: Family of man who died on Benidorm holiday say they have new evidence of foul play
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