Mexican police have arrested 73 people after breaking up a protest by taxi drivers that blocked the main highway leading from Mexico City to Acapulco.

The police chief of the southern state of Guerrero says police found five assault rifles and a bag of cocaine in vehicles abandoned by protesters. Police Chief Pedro Almazan says four federal police officers were injured in Friday's confrontation with demonstrators.

The protesters from the mountains of Guerrero state were demanding increased security in their violence-wracked communities.

However, some residents of the mountain communities were also demanding that the government stop aerial fumigation of opium poppy crops that are common in the region. Local media reported that herbicides are contaminating streams.

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