The search continues for the American tourist who disappeared on Tuesday after he set-off to hike across the island of Amorgos in the middle of a heat wave.

The fire department and volunteers are searching the hiking trail taken by the 59-year-old former police officer, named Eric Calibet, with the assistance of drones, and are focusing on the location where his mobile phone last sent a signal.

According to reports at MEGA TV, the tourist left for his hike at 7:30 in the morning on Tuesday, from the region of Aegiali on Amorgos, with the goal to hike 20 kilometers to the port of Katapola.

According to reports at MEGA TV, the visitor was last seen about halfway through the hike when he stopped at a tavern to purchase a soda and bottle of water, around 9:30-10:00.

The owner of the shop said he saw the man in a good condition, but still offered to call him a taxi to take him to Katapola port, on account of the heat. But the hiker refused, said the tavern owner to MEGA TV.

The hiking trail is considered to be well-worn, according comments made by citizens of Amorgos to MEGA TV. But there are some steep areas and there is no shade on the trail, with the exception of a few caves.

Authorities are perplexed because Calibet has been travelling to Amorgos for years and has taken the trail from Aegali to Katapola several times, with the mayor of Amorgos telling press “he knows the island better than I do.”

The man was declared missing on Tuesday when his friends noticed that he had not yet arrived at his point of destination by the afternoon.

The news of the missing hiker comes on the heels of the tragic death of the world renown Dr. Michael Mosley, from the BBC, who went for a walk on the island of Symi and died on his journey.

Authorities, throughout the country, are already on high alert due to the heat wave that is sweeping the country, which has led to the closure of schools and changes to the working hours of the public sector.

Amorgos is a remote island of the south Aegean region, characterized by its white-washed buildings, rocky terrain and sparse vegetation. It was the filming site of the French movie Big Blue and is also the home of the famous monastery of Hozoviotissa.