Two men have been arrested on suspicion of murdering a father and son who disappeared in Spain five years ago.
Daniel, also known as Danny, and Liam Poole have not been seen since visiting Malaga in 2019, and their case has been treated as a murder probe by Sussex Police since 2022.
A man in his 30s, from West Sussex, and a man in his 40s, from the Merseyside area, have both been arrested, questioned and released under investigation pending further inquiries, the force said.
The move comes weeks after detectives offered a £10,000 reward for anyone with information that could result in an arrest or charge in the case.
Detective Chief Inspector Simon Dunn said: “Although Danny and Liam went missing in Spain, we believe there are people in the UK who may hold vital information about their disappearance.
“We understand there may be some who have felt unable to come forward before now, but it’s not too late to do the right thing.
“You may not appreciate the importance of the information you have, but it could be the piece of the puzzle we need to build the picture of what happened to Danny and Liam.”
The pair, from Burgess Hill, then aged 46 and 22, hired a grey Peugeot 308 with the registration 0254 KTM when they arrived in Spain on March 31 2019, but Spanish police later found the car abandoned, and their luggage and passports had been left at their hotel.
Anyone with information can call 101, quoting Operation Pheasant, or contact Crimestoppers anonymously.