One teen in Maine found more than candy in their bag after trick-or-treating in Auburn this year.

According to reporting in the Portland Press Herald, the parents of a 13-year-old girl called police when the child found a plastic sandwich bag containing what appeared to be marijuana.

News Center Maine reported that the teen was worried that other kids and small children may have also been targeted. The chief of police in Auburn confirmed that the substance was in fact marijuana, and that the teen probably picked it up while trick-or-treating in the area around Auburn Middle School.

Police believe that this is an isolated incident.