Published: Apr 05, 2013 11:02 AM EDT

PHOENIX (AP) - Phoenix police are trying to figure out why a man reportedly got on a bus, rode it to a school and left a gun magazine with 15 rounds of ammunition on the bus.
    
Authorities say the man told an adult bus assistant he was with a boy who had also just boarded the Alhambra Elementary School District bus on Thursday.
    
The man got off the bus but police were called when a child found the magazine.
    
Officers say they later determined that the man approached the boy in his neighborhood Wednesday but was rebuffed.
    
Police arrested 29-year-old Jeremy West after getting tips when news broadcasts reported a description of the man on the bus.
    
West is charged with endangerment, criminal trespass and having a weapon on a school property.

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