Christopher Watts was sentenced to life in prison on Monday for murdering his pregnant wife and their children at an emotional court hearing where he was eviscerated by his in-laws, forgiven by his own parents and where he finally said sorry for the unthinkable killings.

Axar.az reports citing Mail Online.

Watts, 33, appeared in court in Greeley, Colorado, on Monday morning to learn his fate. He accepted a plea deal earlier this month to avoid facing the death penalty.

He was given three life sentences without parole for the murders of his 34-year-old wife Shanann, their daughters Bella, four, and Celeste, three, and for killing his wife's unborn baby son, Nico.

It was the first time prosecutors confirmed his motive: to begin a new life with his girlfriend who he had been seeing for two months before he carried out the murders. Watts killed his wife and children on August 13 in the early hours of the morning.

Afterwards, he dumped Bella and Celeste in crude oil tanks and Shanann in a shallow grave. Their bodies were found on August 16 after Watts went on television pretending not to know what had happened to his family.

Before a judge handed down his sentence on Monday, Watts listened to his father-in-law and brother-in-law deliver blistering statements about him. They dubbed him an 'evil monster' and asked why he 'slaughtered' his family who worshiped him.

New details also emerged about how he killed them. Shanann was strangled and the two girls were smothered.

All three were wearing t-shirts and underwear at the time and that is how they were discovered three days later.

Their autopsies had been under seal but were released on Monday.

Watts was filmed on neighbors' surveillance cameras 'carrying them out like trash' and loading them into his truck to be taken to the oil field where he worked/

He did not speak at the hearing but an attorney said for him: 'Mr Watts has asked us to share this morning that he is devastated by all of this and although he understands that words are hollow at this point, he is sincerely sorry for all of this.'

'You carried them out like trash, you evil monster' said by his father-in-law: