Brother of missing hiker calls for greater U.S. involvement in search

The brother of an American tourist who went missing while hiking on the Greek island of Amorgos is appealing for help.

Albert Calibet, 59, a retired police officer who has dual American and French nationality, was still missing Tuesday after undertaking a solo hike a week earlier. His brother, Oliver, was in Greece with a small group of friends and family to help with the search efforts, and posted a video on YouTube on Monday pleading for more help finding Calibet.

But Oliver Calibet said he thinks the U.S. government should do more to find his brother.

“He’s a first responder, he’s a guy who went missing. He’s a guy who has helped a lot of people throughout his career,” Oliver Calibet said in a YouTube video.

Friends and family of Albert Calibet told CBS News that he was familiar with the island's hiking trails, which he had visited for years.

” That does not make sense. It’s like it swallowed him,” said Sandrine Cutright, Calibet’s sister-in-law.

Robin Winston, a friend of Calibet, said Calibet may have suffered an injury that is preventing him from moving, and stressed the urgency of finding him.

Greece is going through a period strong heatwave, with temperatures topping 104 degrees earlier this month, contributing to the dangers hikers face. The heat waves were so intense that authorities had to close schools.

Calibet is one of several tourists who have gone missing recently on the Greek islands. At least three people have been found dead, including prominent British television doctor Michael Mosley and a 55-year-old man. Toby Leaves from Floral Park, New York. On Saturday, another body was discovered on the island of Samos, where a Dutch hiker had been missing for a week.

According to Reuters, two French women were also missing. One of the women contacted the owner of the guesthouse where she was staying on Friday to ask for help. Ilias Gavanas, the owner, informed Reuters that she sent him a selfie and a message early Friday morning, saying she had fallen.

Meanwhile, even though Calibet hasn't been seen in seven days, his family remains determined.

“I know the chances are probably very slim,” Oliver Calibet said. “But if there’s that 1%… I just want my brother back.”