Three New Mexico firefighters have been charged with gang raping a colleague’s sister — with an affidavit claiming one even searched up, “How long does DNA stay in vagina?”

Albuquerque Fire Rescue Lt. Aden Heyman, 46, Firefighter Angel Portillo, 32, and since-retired driver Anthony Martin, 44, were busted Wednesday and charged with second-degree rape, KOB4 said.

The woman — whose sister worked with the trio — agreed to go to Martin’s home on July 15 after spending the day drinking with him and Portillo at a golf tournament, according to police documents obtained by the Albuquerque Journal.

There, they “were swimming, laughing and having fun” — until Heyman arrived and “the energy shifted,” the women told cops, according to the documents.

She detailed how she “began to fade” — and when she came to, Heyman was “instructing the other two” and “coaching them” on how to assault her, the report said.

She eventually escaped by climbing through a bathroom window and was found curled up and crying outside the apartment complex, the documents said.

After the woman went to police, a search of her relative’s phone showed messages between the victim’s family member and the accused firefighters.

In the days that followed, the trip exchanged text messages vowing to keep quiet about what happened, the documents said.

Heyman allegedly texted that the woman doesn’t “wants people knowing about it … I’ll never say a word about it to anyone.”

“I would hope it doesn’t get out unless the worst happens or we mention it. Which I won’t ever,” Martin replied, according to the documents.

Cops also found messages the men sent to their colleague, the alleged victim’s sister — with Portillo allegedly saying he was “upset with” himself and “one thing led to another and alcohol influenced questionable decisions.”

On Aug. 7 — more than three weeks after the alleged attack — Heyman did a Google search asking, “How long does DNA stay in vagina?,” the docs said.

Martin has since retired, according to KOB4. Heyman and Portillo were both put on administrative leave, their department said, vowing to cooperate with cops.

“The allegations were alarming and we determined a thorough investigation was necessary to determine the facts,” department Chief Emily Jaramillo told the Albuquerque Journa,. saying they “treat these allegations seriously. “

The three men have refused to talk to investigators, the report said. However, their lawyers all denied the allegations, with Martin’s attorney, Ben Ortega, calling the accuser a drug user who is “not credible.”

“As far as I’m concerned, none of these three men did anything wrong and now their careers as firefighters will be tarnished by these allegations,” he said.

Heyman’s attorney Jason Bowles, said the firefighter “has committed no crime and is innocent of these charges.”

Portillo’s attorney, Heather LeBlanc, also said that her client “adamantly maintains his innocence in this matter.”

“As a respected firefighter in our community, he has dedicated his life to helping others,” LeBlanc said.

“He is fully aware of the gravity of these charges and has fully cooperated with law enforcement in the ongoing investigation. We will be vigorously defending against these allegations to ensure that the truth prevails.”

The three men appeared via video link in court Thursday where they were kept in custody, KOB4 said.