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SAN JOSE — An alert passenger helped free two Washington children from a disturbing sexual-servitude scheme after her eyes darted to the smartphone screen of a man exchanging child-sex texts on a San Jose-bound flight, authorities said.

The suspect’s undoing appears to have been the large font he used to read and write the illicit messages, which he reportedly did in plain sight of other travelers, including the quick-thinking woman who reported it to the flight crew.

Police are hailing the passenger, a Seattle-area preschool teacher who asked not to be publicly identified, as a hero.

“It’s kind of mind-blowing,” said San Jose sex-crimes Detective Nick Jourdenais. “She gets on a plane, a normal citizen minding her business. A couple of hours later, she’s intervening on quite possibly the most traumatic thing children can go through. This was life-altering for them.”

She was on a Seattle-to-San Jose flight Monday on Southwest Airlines when she noticed a man sitting directly in front of her texting on his large smartphone, holding the device close to his face and in her line of sight. Jourdenais, who interviewed the witness, said the text messages she saw swiftly escalated from sexual fetishes to far worse.

“It was in large font, and she sees certain words and starts contemplating there’s something bigger there,” he said. “Then the conversation transitions to children. That’s the moment when she decided to preserve the evidence as best as she could.”

She took photos of some of the texts with her own smartphone and then quietly alerted the flight crew. They contacted San Jose police and its airport division stationed at Mineta San Jose International Airport, the destination for the flight.

“Kudos to his young lady. She went a step further,” said Sgt. Brian Spears, commander of the SJPD Internet Crimes Against Children task force. “Without us responding right away, he would have been lost.”

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San Jose police, along with San Francisco-based FBI agents, responded to the call and detained 56-year-old Tacoma resident Michael Kellar. Jourdenais and Michael O’Grady conducted an interview where Kellar freely consented to a search of his phone — he reportedly dismissed his text messages as nothing more than fantasy and role playing. The detectives then contacted their counterparts in Seattle.

The Seattle detectives, and FBI agents from that area, used the smartphone evidence to pinpoint a home in Tacoma where the woman exchanging texts with Kellar lived. That’s when they confirmed that the case was more than outlandish texts, and that two children ages 5 and 7 who lived at the home were being sexually abused.

Investigators contend that Kellar was making sexual requests for the children and that the woman, identified as 50-year-old Gail Burnworth, was carrying them out.

It appears that the woman “had access to children either as a caregiver or babysitter,” according to a statement from the city of Seattle.

Kellar was booked into the Santa Clara County Main Jail on suspicion of two felony counts each of attempted child molestation and solicitation of a sex crime. He is being held without bail.

Burnworth was booked into jail in Pierce County, Washington, on suspicion of felony counts of sexual exploitation of a minor, rape of a child, and dealing in depictions of a minor engaged in sexually explicit conduct.

Jourdenais said the case was a powerful example of how vigilance can take many forms.

“We always preach ‘If you see something, say something.’ It was apparent to her to say something. She wasn’t going to take this home,” he said. “She sees herself as a guardian and protector. It should be acknowledged.”

Anyone with information about the case can contact sex-crimes Detective Nick Jourdenais or Detective Sgt. Brian Spears at 408-537-1397 or leave a tip with Silicon Valley Crime Stoppers at 408-947-STOP or svcrimestoppers.org.

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