Experts explained the reason they believe woman was eaten alive by a bear whilst on the phone to her mum

Experts have weighed in on the harrowing death of a teenager who was eaten alive while on the phone to her mother.

Olga Moskalyova tragically lost her life in August 2011 after she headed out for a summer walk with her stepdad, Igor Tsyganenkov.

The pair had gone out to a river in the village of Termalniy, near Petropavlovsk Kamchatskiy in the east of Siberia, Russia.

They had just gone to retrieve a fishing rod the man had left there previously. But things took a turn when a brown bear launched at them as the teen dodged it before witnessing it attack Igor.

The teenager was found dead. (Family handout)

Olga’s mum, Tatiana, then received a shocking call as the teen shouted over the phone: “Mum, the bear is eating me! Mum, it’s such agony. Mum, help!'

She thought her daughter was joking, but recalled to the Daily Mail: "But then I heard the real horror and pain in Olga's voice, and the sounds of a bear growling and chewing.

"I could have died then and there from shock.”

Tatiana tried to get in touch with authorities for help but received another call from Olga: “Mum, the bears are back. She came back and brought her three babies.

"They're... eating me."

After being left for dead, she called her mum one more time to say she wasn’t ‘hurting anymore’ and asked for forgiveness ‘for everything’ before adding: “I love you so much.”

Olga was soon found dead while the mother bear feasted on Igor’s body.

Theories on just what went down that day have flown around the internet and on the Man Eaters true crime podcast, they rounded up various ‘experts’ opinions on just why the bear ‘ate’ the pair.

The bear may have been protecting her cubs. (Getty Stock)

Firstly, it’s thought that the bear may have been ‘spooked’ by Olga and Igor and therefore attacked them out of self-defence for her cubs. This seems likely as it’s well-known how territorial and protective mother bears can be.

Others however reckon the bear had an injury, preventing her from her usual hunting practice. So, Olga and her stepdad may have been targeted because they were a convenient prey, readily available and not perceived as a threat.

While another theory is that the bear had become ‘habituated’ to human contact. Overall, brown bears are unpredictable animals and will typically only attack if they feel threatened or surprised.

After the pair were found, emergency services called hunters to kill the mother bear and her cubs.

Just half an hour after the killings, Igor's brother, Andrei, appeared at the scene with police, finding the mother bear feasting on his body, with Olga's dead body also on the ground.