MEXICO CITY, April 19 (Reuters) - The U.S. State Department warned Americans on Thursday of increasingly violent drug gangs in Mexico and urged travelers to stick to main highways and well-known tourist destinations.

Mexico has seen a wave of drug-related brutality recently and President Felipe Calderon has sent thousands of soldiers to areas near the U.S. border as well as the resort city of Acapulco to wage war against narcotics cartels.

"U.S. citizens should make every attempt to travel on main roads during daylight hours," the State Department said in its warning, which replaces another issued in January.

Americans should also stay in busy tourist areas and avoid showing off flashy jewelry and large amounts of cash, the State Department said.

Much of the violence is between rival cartels seeking to grab control of drug routes to the United States, but the State Department warned foreigners were also at risk.

To date this year, drug-related deaths number more than 600. A Mexican journalist recently shot in Acapulco died on the doorstep of a popular back-packer hotel.

AlertNet news is provided by