Police in Mexico find a cannon attached to a compressor on an old pickup truck . Cannon was apparently used to carry bags of drugs over the border , authorities say . In a separate incident last year , FBI agents found cans of marijuana plopped in an Arizona field . Cannon is likely to have been involved in that incident , too , U.S. agent says .
Police in Mexico find a cannon attached to a compressor on an abandoned pickup truck . Cannon was apparently used to fire bags of drugs over the border , authorities say . In a separate incident last year , U.S. agents found cans of marijuana plopped in an Arizona field . Cannon is believed to have been involved in that incident , too , U.S. agent says .