The incident took place in Ulster County near the entrance to the Berme Road Park in Ellenville.
After the teen was able to break away and run, the five continued to follow him as he fled the park and beat him again at two other locations including at 244 Canal St., said Chief Phillip Mattracion, of the Ellenville Police.
Two Good Samaritans stopped and screamed at the attackers, who then fled the scene. The two helpers then transported the victim to get help in their car, the chief said.
The Ellenville Rescue Squad treated the boy at the scene and transported him to Ellenville Regional Hospital for treatment.
An investigation found that the boy was repeatedly kicked in the head, punched, and slammed on the ground, causing numerous injuries, Mattracion said.
The assault was captured on video and posted to social media, police said.
Police were able to get a copy of the video quickly and within 15 minutes had identified all of those involved in the assault.
The investigation continued throughout the day and culminated with the arrests of all five suspects, Mattracion said.
Those arrested and charged included two 16-year-old males, two 17-year-old males, and one 19-year-old identified as Devin Harris, of Ellenville, police said.
The 16- and 17-year-olds were charged with one count each of assault. Due to the laws involving youth, they were issued appearance tickets to appear in Youth Court and released.
Harris was remanded to the Ulster County Jail in lieu of bail, Mattracion said.
The victim was treated and released from the hospital.
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