Four teenagers have been charged over a string of robberies in the south-eastern suburbs.
It is alleged that the boys, aged between 15 and 19, used stolen trail bikes when carrying out the offences in Langford, Southern River, Maddington and Gosnells.
A 17-year-old Thornlie boy has been charged with 28 offences including aggravated burglary, stealing a motor vehicle, stealing, reckless driving and failing to stop.
A 15-year-old male, also from Thornlie, has been charged with 24 offences including aggravated robbery, aggravated burglary, stealing a motor vehicle, possessing prohibited drugs and assault.
Both teenagers are due to appear in Perth Children's Court later today.
A 19-year-old Armadale man has been charged with nine offences including aggravated burglary and stealing.
He is expected to appear in Armadale Magistrate's Court today.
An 18-year-old man has been charged with three offences including aggravated burglary.
He is due to appear in Armadale Magistrate's Court on January 31.