ABC:
For years, police have been unable to locate the more than 110,000 missing people in Mexico, but they accompany volunteer search groups that look for such hidden graves. The volunteers, usually the mothers of missing people, often get anonymous tips about where their relatives may be buried.
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the governor of Jalisco state, said an anonymous caller who gave a volunteer search group a tip about a clandestine burial site near the roadway set “a trap” for the officers.
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a total of eight “improvised explosive devices” were planted on the roadway.