Colorado law enforcement officers who investigated the murders of a pregnant mother and her two daughters have spoke out about finding the bodies of Bella Watts, 4, and Celeste Watts, 3, inside an oil tank in August 2018.

As NBC News reports, Colorado Bureau of Investigations and the chief deputy of the Weld County District Attorney’s Office, Steve Wrenn, appeared in season premiere of Oxygen’s “Criminal Confessions” that aired this weekend.

The investigators said they were still shaken by the brutal murder of Shanann Watts, her unborn son, and her two daughters, as they still struggled to make sense of what drove Chris Watts to kill his entire family after he had become romantically involved with a co-worker at Anadarko Petroluem, Nichol Kessinger.

“It was just too strange, too baffling for it not to leave a lasting impact in your head about how does this happen?” Wrenn reportedly said in the episode.

As CrimeOnline previously reported, Watts initially claimed to detectives that he had killed his wife in a rage after he saw her strangle their two daughters. But in early November 2018, Watts made an unexpected guilty plea, admitting to killing all three along with Shanann’s unborn son.

But shortly after the initial claim, Watts told investigators where to find the bodies of his wife and daughters.

“I was completely disgusted. I felt sick. But I was like, we need to go get them. We need to go get them right now,” CBI Agent Tammy Lee reportedly said.

“The first tank was the one that had CeCe in it, she was still in her nightgown … the second tank had Bella inside … I can’t get that image out of my head.”

The investigators did not have further details about the brutal killings until they interviewed Chris Watts months later inside the Wisconsin prison where he is serving multiple life sentences.

As CrimeOnline previously reported, Watts revealed for the first time in that February interview that Bella and Celeste were still alive when he drove with them and their mother’s body to an oil field. It was there that he smothered Bella and Celeste and dropped their bodies into oil tanks, which reportedly had very narrow openings.

“We had never — nobody had ever contemplated that the girls were alive when he drove them out to the oil site,” Wrenn said in the episode.

“Looking at those oil tanks and seeing the size of the hatch at the top and then to have to pull them out of that oil, I wouldn’t wish that upon my worst enemy,” Weld County District Attorney Michael Rourke said.

As CrimeOnline previously reported, Watts has agreed to a civil settlement in which he was ordered to pay Shanann’s parents Frank and Sandy Rzucek, $6 million. An attorney for the family noted that the Rzuceks understand they will likely never see the money, but sought the damages to ensure that Watts could not profit from the killings if he ever sold the rights to his story.

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