Brianna Ghey is said to have killed in "frenzied and ferocious" knife attack by teenage killers.

A UK judge on Friday made the extraordinary decision to lift an order prohibiting the identification of two minors in court after they were found guilty of killing a transgender girl, 16, in a "frenzied and ferocious" knife attack.

Due to the young ages of perpetrators, Scarlett Jenkinson and Eddie Ratcliffe, the killing of 16-year-old Brianna Ghey in Warrington, northwest England, last year in February outraged the nation.

Ratcliffe and Jenkinson, according to AFP, were only 15 years old at the time of attack.

Twenty-eight stabs were made to their victim's head, neck, back, and chest, and her body was spotted by dog walkers in a park.

The youngsters killed the transgender schoolgirl because of their "warped" obsession with torture.

In the UK, under-18 defendants are usually allowed to remain anonymous during their trial; but, if they are found guilty in the most serious case, the media may contest this restriction.

At the end of their trial, Judge Amanda Yip decided to lift the anonymity order, allowing their names to be disclosed at Friday's sentence session.

Following a four-week trial at Manchester Crown Court, Jenkinson and Ratcliffe were found guilty by a jury consisting of seven men and five women after over five hours of deliberation.

Speaking to the two prior to their release from custody, the judge informed them that she was forced to give them life sentences in prison because of their crimes.

"I need to determine the bare minimum of time you must serve before you could be eligible for release," she stated, adding that she would weigh the reports on both sides before making a determination.