Melissa Santana speaks about a trip to Cuba that she led with students from Northern Arizona University in 2016. (YouTube/NAZ Today)

On the morning of Sept. 9, 2016, the inbox of the superintendent of the Flagstaff Interagency Hotshot Crew pinged with a new email. The subject line read: “Your Hotshot Crew Behavior.”

The superintendent, the head of an elite corp of firefighters deployed by the Forest Service and National Park Service to battle wild blazes across the country, had been alerted that morning his team was needed to help with the Soberanes Fire, which was eating through more than 130,000 acres in central California near Big Sur. But by the time the crew’s boss finished the email, according to details laid out in a recently filed criminal affidavit, the Flagstaff crew was grounded.

“I am disgusted by the behavior of your hotshot crew when they passed through my town,” the email read. “Several weeks ago your guys were on the way to a fire in Wyoming. I intercepted messages between your crew members and my UNDERAGE 15 year old daughter. She won’t tell me which website they met on but I did read that they invited her back to their hotel, gave her alcohol and had sex with her. This is statutory rape and I want these men charged.”

The woman, who identified herself as Cathy McCarthy, listed the names of three Flagstaff firefighters who she claimed assaulted her daughter. “I will contact your local papers if I don’t hear back,” she threatened.

The superintendent immediately contacted his superiors. The Flagstaff crew was taken off active service until the allegations were investigated. That same day, Sophia Fong, a special agent with the U.S. Forest Service, was assigned to the case and sent a message to McCarthy at the gmail address she used to contact the superintendent. Fong stressed the Forest Service took the allegations seriously.

When Fong did not hear a reply within three days, the investigator followed up with another email. This time, however, the message bounced back as undeliverable. The account was no longer working. There was no such user, Google confirmed.

And there was no “Cathy McCarthy,” Fong soon established. The allegations of the firefighters having sex with a 15-year-old in Wyoming were also phony, Fong determined. Instead, both the name and email were part of a bizarre skein of threats, fake names and social media accounts allegedly controlled by Melissa Ann Santana, a married, 36-year-old on the interior-design faculty at Northern Arizona University in Flagstaff, Ariz., according to the criminal complaint.

The professor was arrested on Oct. 30 at the NAU campus on federal charges of stalking and making false statements. Federal prosecutors said Santana unleashed a merciless campaign of harassment and intimidation against at least six individuals, including three firefighters, their family members, and even a NAU student. She allegedly wielded as many as 19 fake social media accounts. The harassment reached such a fever pitch her alleged victims were not just deactivating their social media accounts but buying guns for protection and hiring extra security for a wedding.

Santana is in federal custody, and is scheduled to be arraigned on Nov. 29. “We will defend against these charges vigorously,” Santana’s attorney, Stephen Wallin, told The Washington Post on Sunday.

Santana had worked at NAU since August 2012. Last year, Santana led nine students on the school’s first study abroad trip to Cuba. “It’s really cool going into a building from the 1800s and it’s a restaurant or a hotel now,” Santana told the Arizona Daily Sun last year. “I love the concept of keeping old buildings with new uses. It keeps the cultural heritage with architecture.”

The Sun now reports she is no longer employed by the university.

During the investigation into the Sept. 29 allegations, the Forest Service investigator Fong stumbled upon three members of wildfire crews who had previous contact with Santana, an affidavit filed in federal court said. All are only identified by initials. All met her on Tinder, a dating app.

N.L., a member of the Flagstaff crew, admitted to recently ending a sexual relationship with Santana. The two were matched on Tinder in November 2015. Santana used the name”Ann” and stated she was “looking for friends for daytime fun.” They began exchanging messages and meeting up. N.L., however, “became increasingly uncomfortable with the relationship and ended it in June, 2016,” the affidavit said. Santana, however, “did not react well to the termination of the relationship,” and continued to message the firefighter.

That same month, N.L. was matched with another “Ann” on Twitter who was later determined to be Santana. She became insulting, telling N.L. “why not be like the granite mountain hotshots and go die in the fire, like the other dumba– losers there,” in reference to the 19 members of a firefighter crew killed in 2013.

N.L. also found, on separate occasions in August 2016, the back of his car spray-painted and an obscenity keyed into the a car door. In addition, someone posted his phone number to the Las Vegas Craigslist’s casual encounters section with a picture of a woman; N.L.’s phone was bombarded with 20 to 30 text messages and three to four calls from random “men looking to meet up for sex.” N.L. also continued to field angry messages from Santana, the affidavit said.

A second firefighter, S.M., also told Fong he was matched with a woman named “Amanda” via Tinder in September 2016, who made a big scene while he was eating with his crew at a restaurant. The woman, it turns out, was Santana, according to the affidavit.

Soon after, a supervisor on S.M.’s crew received a text message from a number he didn’t know, asking the supervisor to have S.M. contact her. “He won’t return my phone calls, I’m pregnant, it’s his,” the bogus message read. “He needs to take responsibility.” S.M. told his supervisor he did not know what the messenger was talking about. Fong traced the number back to Santana, according to court documents.

The investigator continued to find Santana’s online fingerprints on other harassing aliases and online personalities.

M.G., a Northern Arizona University student, told Fong he received “harassing calls from various unknown numbers, emails and posts on his personal Facebook page and on the Yelp website,” the federal complaint said. “Some of the of the cyber harassment includes a ‘smear campaign’ against him, such as posting falsely that he has STDs.” M.G. told the investigator he had met Santana in December 2014 and that the harassment “began about a week later.”

Like N.L. and S.M., a third crew member, K.T., was also match with an “Ann” in Flagstaff in August 2016. Before the two met, K.T. learned “Ann” was the same person harassing his co-worker, N.L., he broke off communication. But K.T. continued to receive harassing messages from users under different names, including: “Be a success like the granite guys and die at your next fire. “K.T.’s supervisor also received a random text from woman claiming she was pregnant with K.T.’s baby in September 2016.

A year later,  K.T.’s fiance began getting Facebook messages from a woman claiming she was sleeping with K.T. That, too, was Santana, the affidavit said.

The investigator Fong also was contacted by the brother — C.S. — of a man who had connected with “Ann” on Tinder in January 2017. After the brother stood up his Tinder match on a date, she threatened to get revenge on the family. Sure enough, after C.S. and his wife lost a baby due to miscarriage, an unknown user posted on his wife’s Instagram account: “I’m so happy your wife’s disgusting body aborted that bastard child. You two are so superficial that you got exactly what you deserve. A dead baby.”

In the court affidavit, Forest Service investigator Fong described how through Facebook search warrants, comparing IP addresses, and pinging GPS coordinates, she was able to determine “all of the accounts” involved in the above situations “belong to Santana.”

Correction: An earlier version of this story incorrectly noted the location of the Soberanes Fire. This post has been corrected. 

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