Detectives have praised a woman for her bravery which has led to her attacker being given a 19-year prison sentence.
The 21-year-old sexually assaulted the woman in the nearby Jubilee Park.
During the hour-long attack, Mason repeatedly punched her in the face causing her serious injury, and told her he would kill her if she did not cooperate.
The woman managed to escape and ran to a nearby groundskeeper who raised the alarm.
Mason fled but was located later that day by a police officer on South Road, in Durham, where he was arrested and brought into custody.
Detectives charged him with four counts of rape, assault occasioning actual bodily harm (ABH), making threats to kill, and kidnap.
Mason, of no fixed abode, initially admitted one count of rape, plus kidnap, making threats to kill and ABH, but pleaded not guilty to the three remaining charges of rape.
However, after a trial was scheduled to take place, he changed his plea to guilty.
He was jailed for 13-and-a-half years, with an extended licence period of six years at Durham Crown Court on 20 January.
He was also placed on the Sex Offenders’ Register for life.
In a victim impact statement, the woman said: “In the time since I was attacked, I constantly worry about loved ones going out in public."
“I still can’t go out running in public – I have thought about it but feel that I’m not ready.
"I have heard people say: “You shouldn’t go out running or don’t go out running after dark.”
"They just don’t appreciate that it’s not what I was doing – he brutally attacked and raped me, therefore he is the one in the wrong, not me.”
Detectives investigating the case have praised the woman’s bravery and courage following the attack.
Detective Sergeant Stuart Chaney from Durham Constabulary said: “This was a truly shocking and abhorrent incident – the levels of sexual violence used by Mason against an innocent woman were some of the worst I have seen during my 20-year career as a police officer.
"Mason is a vile individual who should be utterly ashamed of his actions."
He added: “I would like to commend the woman for her incredible bravery following this incident. She has shown great fortitude throughout the criminal justice process in being prepared to stand up and give evidence against her attacker.
“I hope today’s result brings her some closure and allows her to move forward with her life.”
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