A former mixed martial arts instructor has been sentenced to 15 years in prison and was declared a dangerous offender after he was convicted of a violent sexual assault on his ex-wife.

Jody Matthew Burke was given credit for time already served in jail, which means he will spend nearly seven more years incarcerated, Noovo Info reported.

Burke's sentencing was delayed this week because he was hospitalized after mutilating his genitals in jail overnight on Tuesday. The offender, who is transitioning from a man to a woman, reportedly did so in an attempt to lower his sentence.

However, the judge, Jean-Jacques Gagné, had indicated that Burke's transition would not affect his decision on sentencing.

One of the offender's victims said in an interview with Noovo Info that she is worried about him being released from custody.

"It worries me a lot," said Brigitte Jobin.

"I don't believe it at all; that story about changing his identity came after the guilty verdict for the first four years he was incarcerated. We didn't talk about it and when he got his guilty verdict, he came up with this scenario."

Jobin said she met Burke in 2016 and that the violence started a few months later, in 2017.

Until recently, Burke was still active on social media despite his incarceration in Montreals' Bordeaux prison. She claimed he was able to 'like' one of her posts.

With files from Noovo Info