Masked demonstrators throw rocks towards riot police during a protest over the 43 missing Ayotzinapa students, near the Benito Juarez International airport in Mexico City on 20 November 2014.
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Mexican students: Mass protests for missing trainee teachers

Family and friends of 43 Mexican students, who disappeared at a protest in September, have arrived in the capital ahead of mass protests.

Mexican authorities say local police handed the students to a drug gang who then murdered them, but some families still believe they will be found alive.

Previous protests have turned violent.

Wyre Davies reports from Mexico City.

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