Bay Village police chief Mark Spaetzel said video of the prank is one of the most disturbing things he's seen in his career, the Northeast Ohio Media Group reported.
"To me, it's reprehensible ... that these kids would take advantage of a vulnerable teenager," he said.
WJW-TV in Cleveland reported this week that the autistic teen's mother discovered the video on his cellphone. She said her son was tricked into having feces, urine and spit dumped on him when other kids told him it was part of the popular fundraiser. She said he was embarrassed and didn't want to tell anyone afterward.
Spaetzel said police are reviewing a copy of the video, which was also posted on social media. He said investigators weren't sure when and where the dumping took place, or how many were involved. But he said all are believed to be Bay High School students.
He said Bay Village police will investigate thoroughly and are moving as quickly as possible to bring criminal charges.
School officials say they will discipline any student who was involved.
Superintendent Clint Keener said the act isn't reflective of the school's student body, which he said has many students who volunteer to try to make sure special needs students have acceptance and success at the school.
"Our entire Bay Village Schools community is heartsick over the cruel actions taken against one of our special needs students," Keener said in a message posted Thursday on the district's website. "The student and family targeted by this act have our utmost sympathy, and we will work to let this student know that we care very much about his well-being."
He also said many students and staff have taken part in the Ice Bucket Challenge to fight ALS, or amyotrophic lateral sclerosis, commonly known as Lou Gehrig's Disease. Celebrities, groups and everyday people have been on the receiving end of dumped buckets of ice and water in the highly popular fundraising campaign benefiting the ALS Association.