Bus vandalism forces another Michigan school district to cancel classes.
This time, the vandalism happened overnight in the Farmington school district, near Detroit.
Police say the air was let out of dozens of school bus tires.
This is the third time in three weeks school buses in Oakland County have been vandalized.
Last month, classes had to be cancelled at West Bloomfield and Waterford school.
Police do not know if the incidents are related.
Another Incident of Bus Vandalism