Police allegedly found a group of children carrying rifles in a pram in Geraldton yesterday.
About 5.40pm, police responded to reports of juveniles acting suspiciously near Gardner Street in Spalding, a north-eastern suburb of Geraldton.
Officers allegedly found the juveniles with a pram which was covered with a rug.
It will be alleged that when the officers lifted the rug, they found five rifles lying in the pram.
A police spokeswoman said officers managed to arrest one of the juveniles after they all fled on foot.
The rifles were allegedly stolen from a home on O'Neil Street about 30 minutes before the Gardner Street incident.
A 15-year-old Spalding boy has been charged with aggravated burglary and stealing.
Inquiries are ongoing and anyone with information is asked to call Crime Stoppers on 1800 333 000.