OSHAWA, Ont. -- Police in Durham Region have charged a special constable for allegedly assaulting a teenaged prisoner.

They say their professional standards unit began an investigation in March.

That's when a youth came forward with a complaint against an on-duty special constable.

Police say Chris Silverthorn, 47, has been a special constable with the service since 2005.

He is currently assigned to court services.

Silverthorn has been charged with assault and was released on a promise to appear.