Two teens in Britain will be sentenced on Friday for killing a 16-year-old transgender girl with a "frenzied and ferocious" knife assault.

The couple, who will be identified publicly for the first time after the judge lifted an anonymity order, murdered Brianna Ghey in Warrington, northwest England, in February of last year.

They stabbed their victim 28 times in the head, neck, back, and chest. Dog walkers discovered her body in a park.

PHOTO | COURTESY Victim Brianna Ghey 

The case received international attention and horror in Britain, especially since the offenders were 15 at the time of the murder.

Under-18s on trial in the UK are usually allowed anonymity, though the media can dispute that limitation in the most serious cases.

Following a four-week trial at Manchester Crown Court, a jury of seven men and five women found the two, now 16 years old, guilty after over five hours of deliberation.

Judge Amanda Yip addressed the couple before returning them to prison for sentencing, telling them she had to inflict life sentences for their convictions.

"What I have to decide is the minimum amount of time that you will be required to serve before you might be considered for release," the judge said.

During the trial, the court heard how the defendants contemplated killing Brianna in the days and weeks leading up to her death.

Jurors found that one of the accused, known as Girl X, had downloaded an internet browser program that allowed her to see films of real-life torture and murder in "red rooms" on the "dark web."

She became interested in serial killers, taking notes on their tactics and admitting to having "dark fantasies" about killing and torture, the court heard.

The couple later drew up a "kill list" of four more teenagers they wanted to hurt, but Brianna had the "misfortune" to befriend girl X, who became "obsessed" with her, according to prosecutors.