The family of missing Russell Bohling believe the discovery of a 'suicide tape' has led police to believe he has taken his own life.

Officers discovered the dictaphone tape shortly after Russell's disappearance but his family insist the tape is three years old and recorded while he was concerned about his future.

The family, of West Ella, have always maintained their belief Russell, 18, was abducted and murdered

They now feel the police have always believed it was suicide and failed to take necessary steps to explore third party involvement.

Russell's father, Roger Bohling, said: "The basis for believing Russell took his own life is the tape and the fact the car was found at Bempton Cliffs.

"We knew at the time Russell was very worried about not taking any exams and anxious he would never find a job.

"But Russell's life changed while at Bishop Burton College. He excelled at his bricklaying course and won the best student award for his year group.

"We also know he had downloaded information about the RAF bas at Bempton, so there was a reason for him being at the cliffs.

"I think their minds were made up by the discovery of the tape and the car's location."

The family have also challenged the police to explain why they dismissed a fuel discrepancy.

The family believe Russell's car must have been refuelled between him leaving home and driving to Bempton Cliffs because of the amount of diesel left in it.

But Russell's debit card had not been used and he had very little cash on him, suggesting a third party provided the money.

The family have recreated the journey using the 3.8 litres of fuel allegedly used and ran out 20 miles short of Bempton at Brandesburton.

Russell's brother Andrew said: "We knew it was not possible for Russell to travel to Bempton on that amount of fuel and we told the police.

"As a result, they allowed CCTV at the garages along the way to be destroyed. It doesn't make sense."

Mother Christine insists the focus of the investigation is wrong.

She said: "I think there must be someone else involved but the police refuse to look into this. The refuelling issue is so significant."

Russell was last seen on March 2 after leaving the house to go to college.

His blue Clio was found the next day at Bempton Cliffs.

Mr Bohling insists their concerns are based on facts and not emotions.

"People may think we are just overwrought parents who can't come to terms with their son's death," he said.

"But we have looked at the balance of probabilities. We are not dealing in speculation but in mathematics."