Friends who vanished while hiking left disturbing photo evidence on their phones

The disappearance of Kris Kremers and Lisanne Froon was a mystery that was discussed for years but photos discovered later on added another confusing element to the story.

Kris Kremers, 21, and Lisanne Froon, 22, had been planning a hiking trip around the jungle in Panama for months before they disappeared on April 1, 2014.

The pair are believed to have gone for their hike through a forested area near the Baru volcano in Boquete, Panama back in 2014 but were never seen again.

What exactly happened to the two women has continued to spark debate on social media, with many people offering their own suggestions as to the fate of the two friends.

Not long after the pair disappeared, a backpack with their phones, camera, money and items of clothing washed up by the side of the Culebra river.

Some have accused the police of botching the investigation at the time (YouTube)

The phones had remained working for some time after their disappearance, with police discovering the two friends had made a total of 77 calls to emergency services, to no avail.

Meanwhile, photos discovered on their camera added more details to the incident but gave few answers.

A series of photos were discovered on the camera, including a number which were almost completely dark and had clearly been taken at night.

Several of the pictures had been taken at night (TVN2)

Some of the pictures show the women's belongings spread out on some rocks next to a plastic bag and wrappers, while another appeared to show the back of Kremers' head.

Other have suggested that the two young women had been involved in an accident and Kremers had died when trying to get help for herself and Froon.

This idea further emboldened when later that year when fragments of bone belonging to the women were found.

While Froon's bones seemed to have decomposed naturally, strangely Kremers' appeared to have been bleached due to their stark white appearance.

Two Dutch authors believe they have solved the mystery of the two women.(TVN2)

Dutch authors Marja West and Jürgen Snoeren claimed that their book, Lost in The Jungle, solved the mystery.

West said: “Our conclusion had to be that it was an accident. It took us quite some time to get there.

“Once we had the files, we could understand where people outside the investigation got sidetracked and why.

"The police were inundated by tips, each had to be checked out, losing them valuable time. It became a hell of a job."

No official cause of death has been ruled due to lack of evidence.