The family of a young gamekeeper believed to have shot himself after accidentally killing his girlfriend said the 18-year-old would be "loved and treasured forever".

Grampian police confirmed that the man shot dead in the Highlands village of Tomintoul on Tuesday evening was Calum Murray, 18, from Tillyfourie, in Aberdeenshire.

The trainee gamekeeper is understood to have killed himself in distress after accidentally shooting his 16-year-old girlfriend, Sophie Taylor, as he was cleaning his shotgun in a cottage on the sporting estate in the Cairngorms where he worked.

In a brief statement, his family said: "Calum was a much loved and loving son, brother, grandchild, nephew and friend to many. He completed a cookery course before embarking on a career as gamekeeper. Calum was very passionate about his new career. He loved the outdoors, walking with his dogs in the hills and had shown a real flair and desire to progress with his gamekeeping.

"Calum was much admired both by his family and his friends and we are very proud of all he had achieved. He will be loved and treasured forever."

Police are still investigating the full circumstances of the tragedy. It is understood the incident was witnessed by two friends of the couple, another gamekeeper and his wife.

Local people who knew those involved said the couples had been having tea after both men had finished work. Taylor was killed instantly after the shotgun went off. The other man tried but failed to stop Murray running out of Blairnamarrow cottage and shooting himself.

A fourth-year student at Speyside high school in Aberlour, Taylor was about to sit her standard grade exams. She wanted to become a social worker, her family said. Students at the school are to be offered counselling and a memorial assembly will be held after her funeral.

David Tierney, the headteacher, said: "It's been a very great shock to everyone to hear of Sophie's death. The thoughts of everyone at the school go out to Sophie's family. Sophie was positive, enthusiastic and a popular pupil. Her great strength was that she got on with everyone, pupils and staff."

Sheona Finnie, one of the owners of the Glen Avon hotel in Tomintoul, where Taylor worked part-time as a waitress, told a local radio station, Moray FM, that the teenager was "a good girl, good fun to be with and to spend time in the kitchen with. You always had a good laugh with Sophie."

She added: "I don't think it's sunk in to everybody – all my staff are in shock. They're all finding it really difficult. I spoke to her mum yesterday morning. I think they're doing as well as can be expected. I don't think there's any way you can deal with a tragedy like this. Everybody knew Sophie and we all know the family. We all are close in the hotel so we all support each other, look after each other."

Murray was in the first year of a two-year gamekeeping and wildlife management course at North Highland college in Thurso, and had been working at the Glenavon estate near Tomintoul as part of the course.

Gordon Jenkins, principal of the college, said: "Our hearts and thoughts go out to the families of both young people who were killed. [The] tutors I have managed to speak to say he was a model student. This is a great loss to the college, his course and the estate he was employed on. Everyone is shocked and saddened by what has happened."