I hope, just for a moment, my sister's murderer felt as frightened as she did in her final moments

"Just for a moment, he may have felt as frightened as Sasha did". Those were the words of Katie Brett, sister of murdered Blackpool teen Sasha Marsden, speaking for the first time after killer David Minto was brutally attacked by another inmate in Wakefield Prison.

Earlier this month, fellow killer Duncan Heaton was convicted of attempting to murder Minto at the jail dubbed "Monster Mansion" which houses some of Britain's most violent and perverted prisoners.

Now papers released following 53-year-old Heaton's trial at Leeds Crown Court, reveal the killer hated Minto because he's a sex offender. Heaton battered and stabbed Minto with improvised weapons after calmly strolling into the Blackpool killer and rapist's cell.

Leaving Minto covered in blood, Heaton then walked into a guard's office on the wing and said: "I've done Minto, I've done the Blackpool nonce." Heaton, who is serving a life sentence for stabbing a disabled man to death, said he singled out Minto because he hated sex offenders and "had family in Blackpool".

He had spent a fortnight planning the attack on Minto, who murdered and raped 16-year-old Sasha in 2013. Afterwards, Heaton said he had only stopped the attack because he believed Minto was dead, adding that he would have returned to finish the job if he knew he was still alive.

At his trial, Heaton asked for a whole life sentence, however, he received an extra 13 years for the attack on Minto and a paedophile in Full Sutton Prison. In the year's following Sasha's death, Katie campaigned for the implementation of Sasha's Law which would give grieving families longer to appeal against the sentencing of killers like Minto.

Last month she celebrated as Parliament enshrined it in law. Previously families had only 28 days to lodge an appeal. She said: "Is it right that this evil individual one day gets a chance at rebuilding his life and starting fresh?

"We will never get over what happened to Sasha. It has scarred us for the rest of our lives, but one thing that makes living with this even worse is living with the knowledge that one day he will be free to kill someone else's daughter."

Minto was sentenced to life with a minimum tariff of 35 years for the brutal rape and murder of Sasha, who was studying childcare. On the day of her death, Sasha had been dropped off at Blackpool's Grafton House Hotel, where Minto worked as a caretaker, believing she was there for a job interview.

There were no jobs at the hotel, which was closed and under renovation, she had been lured there by Minto. He stabbed her before raping her and dumping her body in a South Shore alley. She had been stabbed 58 times and sexually assaulted both before and after she died.