Residents have returned to their homes after being evacuated and police are investigating the origins of what is believed to be a bomb found in Lalor Park yesterday.
Police said they received a call from a resident about 1.45pm, yesterday, reporting a suspicious object planted on top of a letterbox in Commercial Road.
Detective senior sergeant Wayne Kelly said the bomb squad were called to assess the object and defuse any bomb threat.
He said the bomb squad x-ray scanned the bomb to determine what it was made from.
The object was described as a can of soft drink with wires sticking out of it.
Bomb squad officers sent in a robot to remove the object from the brick letterbox where it was left and it was taken away for more examinations.
Detective senior sergeant Wayne Kelly from Blacktown police said no threats or attempts at extortion had been made to police or residents.
He said the bomb may be a prank by school-aged youths on holidays. Police are continuing their investigations.