Killer Chris Watts has opened up about the murder of his wife and affair with his mistress in an interview with the Colorado Bureau of Investigation. Watts is serving three life sentences for killing his pregnant wife and two young daughters.

Watts told investigators during the released interview about the details that lead up to the death of his wife Shan’ann , who he strangled in their bedroom.

According to Watts, “I woke up that morning and I knew I had to do it. Why couldn’t I just let go? I don’t want to know what she saw when she looked back at me.”

When investigators asked Watts if he looked at Shan’ann when he strangled her, he confirmed that he did, saying, “Yes. She wasn’t fighting. Maybe she was praying. Maybe she was saying scripture. There wasn’t any defensive wounds because she couldn’t fight back. I just got on top of her and that was it. It is in my head, in the back of my head, that was going to happen.”

The murder of Shan’ann was proceeded by an argument with Watts, where he told her he was having an affair and wanted a divorce. Shan’ann told Watts that he wouldn’t be able to see his children again, which allegedly enraged him.

Watts knew the day that he killed Shan’ann that he was going to do it as he told investigators that he wanted to be together with his mistress Nikki Kessinger.

“With Shan'ann I never felt like I could be myself,” he said. “But with Nikki I could be myself. Nikki just wanted sex all the time, she wanted it when she wanted it. With Shanann it was just like okay.”

Watts was with Shan’ann one last time, where he then told investigators that “I told her I didn’t love her anymore. She told me to get off of her. She told me that I was hurting the baby. I felt like I could get off of her but I stayed on top of her. With everything that happened that morning, I just keep going back in my head. I didn’t want to do it, I just did it.”