Guam's public school system is toughening its bag policy to help deter students from sneaking weapons, drugs or other dangerous items into schools.
The Pacific Daily News reports that in a few weeks, public high school students will only be allowed to use transparent bags on campus, helping school staff quickly scan for such contraband.
A steady increase in safety violations at Guam's public schools led to the firing of the Guam Education Superintendent earlier this year.
Guam's Education Department put in place a temporary ban on all bags and drink bottles at high schools in 2006 after a series of bomb threats.
One chemical explosion led to the hospitalisation of three students.
The new tightening of school security will also provide for random searches of lockers.
