Mexican drug cartels are reported to have taken over control of the very lucrative U.S. illicit drug trade from Colombian cartels.

A similar article published in two popular U.S. newspapers, USA Today and Christian Science Monitor says the Mexican groups have used profits from border delivery routes to grab control from Colombian drug producers.

Another reported reason for the change is successful enforcement against Colombian drug lords by Colombian and U.S. authorities.

The director of the Bush administration's drug control policy, John Walters is quoted as saying the Mexicans are now running crime and "getting the bulk of the money" as "the Colombians have pulled back."

Earlier this week, the governors of the U.S. states of New Mexico and Arizona declared emergencies on their border regions with Mexico, in large part because of an increase in drug trafficking and violence as rival cartels fight for control of transit routes.

Some information for this report provided by Reuters.