KUSA — The body of Shanann Watts, the Frederick woman whose husband is suspected of killing her and their two young daughters, was found in a shallow grave, according to court documents obtained Saturday by 9Wants to Know.

An earlier court filing suggested the two children, Bella, 4, and Celeste, 3, may have been strangled and asserted that their bodies had been found in oil holding tanks.

The disclosure that Shanann Watts’ body had been buried in a shallow grave came in a court filing by Weld County District Attorney Michael Rourke in response to earlier motions by attorneys for Chris Watts.

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His lawyers asked that specific DNA testing be performed and that they be allowed to have a defense expert present for all scientific testing. In addition, prosecutors believed that defense attorneys would seek to have an expert present at the autopsies of the victims, according to court documents.

“The body of Defendant’s wife was located earlier this morning after being recovered from a shallow grave near an oil tank,” Prosecutors wrote in the motion, which was filed late Thursday. “Later this afternoon, law enforcement recovered the bodies of Defendant’s two daughters from inside oil tanks located near the grave of their mother. The Weld County Coroner has informed the prosecution that time is of the essence in conducting the autopsies, especially for the children given the period of time their bodies were submerged in oil.”

Watts, 33, was being held without bail on suspicion of three counts of first-degree murder and three counts of tampering with a deceased body in the killings of his wife and daughters.

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The deadline to file charges is Monday, and the Weld County District Attorney has scheduled a press conference at 4 p.m. that afternoon to announce formal charges against Chris Watts. 9NEWS plans carry that press conference live online and on our social media pages.

Defense attorney James Merson wrote in one of two motions obtained by 9Wants to Know that he’d spoken with a DNA expert, Richard Eikelenboom. According to the filing, Eikelenboom told him “that even though the bodies of two of the decedents have been in an oil well filled with crude oil for several days, DNA would still be present.”

In one of the motions, Merson suggested that time was critical, writing, “The autopsies for this case are scheduled to begin in 20 minutes.”

That motion was filed at 9:55 a.m. Friday.

In an attachment to the motion, Merson included an e-mail in which Eikelenboom expressed his “expert opinion that DNA evidence would remain on the necks of the decedent children in spite of the fact that the remains were in oil for four days.”

“In my opinion, the presence of oil will not destroy the DNA,” Eikelenboom wrote, according to one of the motions.

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Shanann Watts and her daughters were reported missing on Monday.

Chris Watts initially said his family was asleep when he left for work early Monday morning. After a friend stopped by to visit Shanann Watts on Monday and got no answer at the door, they were reported missing.

On Wednesday, police took him into custody. A body believed to be Shanann Watts’ was found first. The bodies of the two girls were recovered late in the day Thursday.

One of the defense motions expressed the fear that no one planned to swab the necks of the children’s bodies for DNA.

It also asked for testing of Shanann Watts’ hands in an effort to find evidence.

“The hands and nails of the mother should be sampled as well,” Eikelenboom wrote, according to the motion. “After samples are taken, the nails should be cut preserved.”

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.