Newly obtained court documents reveal the alleged text message conversation about child sex abuse between a Tacoma, Washington, man and his girlfriend while he was flying from Seattle to California on July 31.
Authorities said that same conversation was spotted by a fellow passenger on the man’s Southwest Airlines flight, leading to his arrest when he landed.
According to a federal criminal complaint obtained by PEOPLE, the man, 56-year-old Michael Kellar, and his girlfriend, 50-year-old Gail Burnworth, discussed drugging the kids with Benadryl and molesting them while they slept.
Federal investigators claim the lurid texts were exchanged between Kellar, a divorced father of two, and Burnworth as the former was traveling to San Jose.
The complaint shows the couple, who met online, were allegedly discussing plans to drug and sexually assault two children, ages 5 and 7, to whom Burnworth had access.
In one exchange, Burnworth told Kellar her sexually graphic plans for one of the kids, the documents claim.
“…you can do this or are you just saying this???” Kellar allegedly asked, to which Burnworth allegedly responded:
“No I think I can do it if I don’t have parents over my shoulder or worried about who’s going to walk in on me And then on Sunday I will have the kids no parents just kids,” according to the charging papers.
“You’ll have to give them lots of Benadryl,” Kellar replied, the complaint alleges.
Investigators also found text messages from Kellar allegedly requesting videos of Burnworth “engaged in bestiality, fetish behavior involving feces” and “kid videos,” the complaint states.
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The couple’s plan was foiled after an alert passenger, who was sitting behind Kellar, leaned forward to look out the window and saw the sexually explicit text exchange and snapped photos, federal authorities allege.
“I don’t know how I saw it, I just saw in big text ‘child in their underwear,’ ” the woman, who remains unnamed, told the Mercury News. “I thought, ‘What did I just see?’ My heart started racing. Then I could see more texts coming in.”
In a statement to PEOPLE, Southwest said it was “working with local authorities as part of the investigation. We always encourage our customers to report suspicious activity to employees or law enforcement.”
After the passenger took photos of the texts as proof, she alerted a flight attendant who contacted authorities at the San Jose airport. When the plane landed, an airport officer arrested Kellar.
He initially told detectives that he had been participating in “fantasy role playing” with Burnworth, Seattle Police Department Capt. Michael Edwards previously told PEOPLE. “That is how he tried to explain it away.”
Confronted by investigators in Tacoma, Burnworth allegedly acknowledged that she had a sexual interest in children and admitted to previously sexually assaulting one of the victims on camera and taking nude photos of the other victim and then sending the videos to Kellar.
On Monday, the U.S. Attorney’s Office charged Kellar and Burnworth with attempted enticement of a minor and conspiracy to produce child pornography.
Kellar remains in custody in San Jose awaiting extradition to Washington. Burnworth is also in custody and has a detention hearing on Thursday in Tacoma. Neither has entered a plea.
It was not immediately clear if he has retained an attorney. Her attorney could not be reached for comment.