Mexico killings: Taxi drivers gunned down Gunmen have shot dead at least seven taxi drivers on the outskirts of the industrial hub of Monterrey, which has become one of Mexico's most violent cities during a turf war between rival drug cartels. The taxi drivers were killed as they waited at two depots next to their Volkswagen Beatle cars in the municipality of Guadalupe, six kilometres from Monterrey's centre. Police officers at the scene said they did not immediately know the motive for the attack, which bore the signs of a gangland killing. Gangsters in Mexico have targeted some taxi drivers over extortion payments, while others have been alleged to work as spies for drug cartels.