The brother of murdered Bobbi-Anne McLeod's shouted "you're a dead man" as her killer was jailed for life.
Bobbi-Anne, from Plymouth, disappeared after leaving to catch a bus close to her home on November 20 last year.
Her body was discovered in woodland in Bovisand, Devon, three days later.
Today her killer Cody Ackland, 24, was jailed for a minimum of 31 years.
There were calls of "murderer" and other profanities as Ackland was taken from the dock with Bobbi-Anne's brother Lee shouting: "You're a dead man!"
Mum Donna wept throughout the hearing, reports Plymouth Live.
Judge Linford thanked Bobbi-Anne's family and friends and said he didn't know how they contained themselves.
He added that there is a strong possibility Ackland will never be released.
Judge Linford described how there was substantial planning by Ackland over committing murder in general.
He said: "You were quite clearly planning murder and did murder."
"There were effectively four attempts to kill her," Judge Linford said.
He said they were the initial attack at the bus stop, Ackland trying to strangle Bobbi-Anne in his car, attacking her again with the hammer on the moor and standing on her throat.
He added: "This was a prolonged, savage and merciless attack. It caused outrage and fear in this part of country and rightly so. Utterly motiveless."
He said: "Bobbi-Anne was just 18 when on November 20 you encountered her at bus stop in Leigham area. She had the whole of her life in front of her until it was brutally and savagely snuffed out by you.
"She was a much-loved daughter and sister and a well-liked friend to many. She was the light of the family home, loving, loyal and the best daughter her parents could have.
Her family struggle to comprehend a future without her."
Judge Linford went on to describe how evidence disclosed Ackland had "a worrying and disturbing interest in serial killers".
He spoke of images on his phone including pictures of bodies, post mortems, serial killers. He said: "I am satisfied your interest in this material went beyond morbid fascination."
He added that Ackland was actively looking for tools that could be used to kill and dispose of a body and that his search history included evidence of him searching remote and wooded areas on Dartmoor.
In an emotional statement read outside Plymouth Crown Court, Bobbi-Anne's family thanked those who have offered support and police who brought her killer to justice.
The statement read: “Bobbi was a beautiful girl who lit up our lives and the lives of everyone she ever met. She was kind, funny, and loyal.
"She was the best daughter, the best sister, and the best friend to so many people. Everybody who knew Bobbi loved her. We have been robbed of our beautiful girl in the worst possible way and our lives will never be the same without her."