A Danish teenager and her Muslim boyfriend were convicted of murder Tuesday after allegedly stabbing her mother at least 20 times with a kitchen knife in October after obsessively watching YouTube videos showing beheadings carried out by ISIS members, according to the Independent.

Lisa Borch, 15, and Bakhtiar Mohammed Abdulla, 29, were said to be lovers who wanted to leave Kviseel, Denmark, and go to Syria to fight for ISIS.

Borch first became interested in the terrorist cult after falling in love with an Islamic extremist who then left her heartbroken after returning to his wife and children, reported Breaking 911. She then found Iraqi Abdulla at a refugee center near her home and became enamored with him.

However, constant squabbles between Borch and her mother, Tina Römer Holtegaard, over her relationship with Abdulla had them all on edge.

After brutally killing her mother, Borch called the police. “I heard my mother scream, and I looked out the window and saw a white man running away,” she reportedly told cops. “Please come here, there is blood everywhere.”

When police arrived at her house, they found Borch on her computer. The unconcerned teen, showing no emotion, simply pointed upstairs when asked where her mother’s body was, which immediately made her the prime suspect, reported the Daily Mail.

During investigations conducted after the murder, authorities discovered that Borch had been watching the beheadings of British hostages David Haines and Alan Henning repeatedly on her computer — including right before the mother’s bloody body was found, according to the Independent. Additionally, the fingerprints of Abdulla — who was not at the house when police arrived — were found in Holtegaard’s bedroom.

In court, the teen’s twin said she had moved out of the house because of the constant fighting between her mother and sister. She also said that, at one point, Borch showed her a knife she claimed she was going to use to kill their mother. She thought her sibling was just joking, reported the Mirror.

“This murder was cold-blooded, ice cold and committed in a bestial manner,” said prosecutor Karina Skou in court.

Since it could not be determined who actually delivered the fatal wounds, both Borch and Abdulla were convicted of murder. The blonde teen was sentenced to nine years in prison, and Abdulla received a 13-year sentence (after completion, he will be exiled from Denmark), reported the Independent.