FEARS are growing for a group of ten tourists who vanished while hiking on a bear-infested island.

The hikers – nine women and a man – have now been missing for two nights on Iturup island in Russia’s Far East.

The group had set out on an 11-day trek to summit the 3,714ft Baransky volcano, which remains an “active” threat.

They were briefed by guide Valery Fedosov, 36, from St. Petersburg, but the tourists reportedly did not register their trip with authorities beforehand.

The Russian hikers “stopped communicating” on Saturday night, raising alarm bells.

Before embarking on the hike, the group were given clear instructions from Fedosov about the threat of brown bears on the island.

The guidance reads: “Our best friends during the hike are noise, mass participation, and all the necessary props for scaring off bears, which will be kept by the guides.

“Good news – the probability of meeting bears on our route is very low.

“In four years of hiking, we have met them only three times, and then from afar.”

An estimated 600 wild bears roam Iturup island, whose ownership remains a point of dispute between Russia and Japan.

The island – about the size of Cornwall – is home to an active volcano that last erupted in 1951 and has also experienced hydrothermal explosions.

It’s notorious for its thick fog, which has made rescue efforts challenging.

The remote island is also said to have patchy communication services.

The group failed to catch a bus scheduled for Saturday evening after their climb.

By midnight Sunday, they still hadn’t been located.

Local official Marina Kuzmina said: “They did not come to the [meeting] point, the guide waited for them there for about six hours.”

She added: “The group consists of 10 people – nine women and one man, the escort.”

Among the missing tourists is Dr Ekaterina Kaynova, 32, a surgeon, Dr Irina Tyulkina, a beauty therapist, Regina Belal, 33, a university research fellow and Polina Podolyako, 29, a housing manager.

Officials are furious that the guide did not inform authorities about the trip.

The head of the Kuril islands, Konstantin Istomin, has taken the search into his “personal control”.

“Rescuers, interior ministry officers and a representative of the district administration have been brought in to conduct the search,” he said.

A criminal investigation has been launched by the Sakhalin Region Investigative Committee to determine if the group broke any rules and to look into suspicions that the guide may have had no prior knowledge of the island.

Meanwhile, the guide’s wife, Anastasia, was reported to be on the tour, but she’s not listed as missing.

Another tourist, who had medical issues, stayed behind at the base camp and was later taken to hospital.