HOLMES BEACH, Fla. (WFLA) – A Sarasota County teen was arrested and accused of brutally beating a Manatee County man who was on a walk with his niece.

According to the Holmes Beach Police Department, 18-year-old Cameron Evans was arrested at his home in Sarasota County and has been charged with aggravated battery.

According to police, Evan Purcell, 40, of Holmes Beach, was walking his dog at Anna Maria Elementary School alongside his niece when he came across a group of teenagers drinking and possibly vandalizing the school.

Purcell’s family told 8 On Your Side the 40-year-old is disabled and was walking his service dog at the time. According to a news release, Purcell yelled at the teens to stop and move along.

Police claimed the group became aggressive and approached Purcell, who pulled out a pocket knife in fear for his safety.

According to police, the teens knocked Purcell to the ground as they struck him in the head with a wooden object and possibly a skateboard and beat him until he was knocked unconscious.

A 17-year-old boy was also arrested and has also been charged with aggravated battery. A third juvenile has also been charged.