The parent of a teenager from Long Island who had disappeared for a month turned to Facebook over the weekend to express gratitude to those who provided tips and the police officers who helped him locate his missing child.

Frank Gervasi, in a video shared on Facebook shortly before 1 p.m., revealed, “She is currently receiving the necessary assistance in a facility and is safe.” Speaking about his 14-year-old daughter Emmarae, he continued, “I want to express my appreciation to the community for the immense support you all offered.”

It was “social media videos and (donated) flyers” that led to an anonymous tip from a woman that helped him find his daughter, Gervasi said.

Recalling the moment he received a crucial phone call, Gervasi mentioned, “I was informed that she was spotted on a boat in Islip,” noting his initial skepticism. “The individual who provided me with the tip was hesitant to approach the boat,” he added.

Gervais said he “busted” onto the boat in a marina near the White Cap Fish Market in Islip Friday and retrieved his daughter. He said no one else was on the boat at the time.

“Persistency brought her home,” Gervais said, indicating there may be more than one person under investigation. He believes she had been with “some dangerous people.”

Emmarae had run away from home at least once before, and had had some “struggles” in her life, Gervasi told The Post Saturday.

He said she is now being cared for in a hospital where she is “detoxing.”

He declined to give further details.

“The fact that she’s safe and alive is amazing,” Gervasi said. “It was so incredible to hold her in my arms after I found her.”

Emmarae vanished Dec. 9 after getting into a strange car outside her Patchogue home around 5 p.m., leading her family to fear she was being held against her will.

Gervasi was last seen walking out of her house without a jacket or shoes on before getting into the car, according to Greater Long Island.

Security cameras captured her knocking on doors at a Bohemia motel the next day, but she disappeared again.

Gervasi said his daughter initially went off with a man she met online, but left him before she was then picked up by a “random” 65-year-old man she didn’t know, he said.

He believed Emmarae had been told she couldn’t leave the boat.

Gervais said he wants to begin helping other families on Long Island who have missing children.