Mexican army patrol drug-city

Security is stepped up in Mexico's most violent city Ciudad Juarez.

Armoured vehicles replace police cars in the Mexican border city of Ciudad Juarez.

The city is known as Mexico's most violent where 2000 people were killed last year in drug related feuds.

The government has asked the army to step in to heighten security in the city.

This resident says it makes him feel safer.

(SOUNDBITE) (Spanish) RESIDENT, WALTER OROZCO, SAYING:

"I like them to do this because one can feel calmer, one travels without fear, or anything, it's good, they stopped me and inspected me and everything, but I have nothing to hide. I think this operation is good."

Mexican authorities fear the violence could spill over into the United States.

Washington said it will support the efforts of Mexican President Felipe Calderon.

(SOUNDBITE) (English) GEOFF MURRELL, PENTAGON SPOKESMAN, SAYING:

'' He is using the Mexican military to deal with what some would argue is an existential threat to his government and so we have pledged through the Merida Initiative to support the Mexican military, the Mexican government, in their efforts to combat this threat."

Ciudad Juarez is a major battleground in Mexico's drug war with the army taking more control of security as police are often bribed to join the cartels or killed.

Basmah Fahim, Reuters.