Authorities in Mexico have arrested 14 people accused of belonging to the Zetas drug cartel in the northern city of Monterrey.

The gang has become the largest in the country, making its money by trafficking drugs and carrying out kidnappings and assassinations.

But some Mexicans in rural areas have become frustrated by what they see as a lack of response by the authorities to the drugs violence and have formed their own vigilante groups.

Beth McLeod reports.