Children were handed packets of cocaine instead of sweets on a Halloween trick-or-treating trip, Greater Manchester Police have said.
Police were called after children found the class A drug among bags of sweets after visiting Mendip Close, Royton, at 19.50 GMT on Wednesday.
Two snap bags of cocaine were recovered by police.
A 33-year-old man from Royton has been charged with possession of class A drugs and is due in court on Friday.
The accused man is set to appear before magistrates in Oldham.
A 21-year-old woman was arrested on suspicion of possession of class A drugs and later released without charge.
Supt Catherine Hankinson said: "The parents and police acted quickly when this report was made, in the interests of public safety.
"We understand this to be an isolated incident."