Rex Heuermann is already in trouble behind bars.

Rex Heuermann is already in trouble behind bars.

The convicted Gilgo Beach serial killer was reportedly disciplined after correctional officers accused him of drug possession and attempting to smuggle a package into prison.

The alleged violations happened in July — just weeks after Heuermann was sent to prison to begin serving multiple life sentences without the possibility of parole.

Additional reporting indicates officers discovered a small piece of paper that allegedly tested positive for a synthetic drug.

From Gilgo Beach to one of New York's toughest maximum-security prisons — the Rex Heuermann story apparently isn't finished yet.