Chris Watts' Alleged Lover 'Is Cooperating' with Triple Murder Investigation: Source

The co-worker with whom Colorado murder suspect Chris Watts was allegedly "actively involved in an affair" has been cooperating with police, a source says

The co-worker with whom Colorado triple murder suspect Chris Watts was allegedly “actively involved in an affair” at the time his wife and daughters were killed has been opening up to police, PEOPLE confirms.

A source close to the case confirmed to HLN’s Crime & Justice with Ashleigh Banfield on Tuesday that the co-worker — a woman — has met with investigators at least once and “answered all their questions.”

PEOPLE confirmed that report with a separate source.

“She is cooperating,” the second source says, adding that the co-worker is not suspected of any criminal wrongdoing.

The alleged extramarital relationship was first revealed in an arrest affidavit released after Watts, 33, was accused of killing his 15-weeks-pregnant spouse, Shanann Watts, and their two children in their Frederick home.

At the request of Chris’ attorney, several lines in the affidavit paragraph about the affair were redacted, though it is unclear why. The co-worker has not been publicly identified.

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A motive in the murder case remains unconfirmed as Chris’ suspected infidelity draws scrutiny. Those who know the Watts family have described a seemingly happy union possibly beset by mounting tension.

Chris faces first-degree murder charges, among other crimes, in the killings of Shanann, 34, and their kids, 4-year-old Bella and 3-year-old Celeste.

He had initially denied the work affair to police, his arrest affidavit alleges. But authorities said they carried out a two-day investigation and confirmed the cheating.

Shanann, Bella and Celeste were reported missing on Aug. 13. Chris was arrested late on Aug. 15 and, on Aug. 16, authorities announced the bodies of his wife and children had been recovered on property belonging to his former employer Anadarko Petroleum.

Shan’ann Watts (right) and her daughters. Shanann Watts /Facebook

Chris Watts. Joshua Polson/AP/REX/Shutterstock

Chris’ marital impropriety was one of several blockbusters allegations in his arrest affidavit.

The affidavit also states that Chris claimed he killed Shanann in a “rage” after he told her that he wanted to separate and then witnessed her strangling daughter Celeste.

He said he also saw Bella lying lifeless and “blue” nearby, according to the affidavit.

However, a source close to the investigation previously told PEOPLE, “The theory that she [Shanann] did it doesn’t hold any water. There is absolutely no evidence that she killed her children.”

Chris’ co-worker is not his only alleged lover whom authorities have interviewed: Last week, an unnamed man came forward and spoke to HLN’s Ashleigh Banfield about a 10-month relationship he claimed to have with Chris before they split in the spring.

Authorities confirmed to PEOPLE that they have interviewed this man as well.

Chris is being held without bond in the Weld County Jail. He has not yet entered a plea.

His lawyer did not respond to PEOPLE’s requests for comment but, according to a statement from the state’s public defender’s office, their attorneys are barred from discussing ongoing criminal cases.