For decades, American and Canadian expats have flocked to the shores of Chapala, seeking refuge in the spring-like climate of Mexico's largest natural lake, where English author DH Lawrence once came for inspiration. But the calm of the clustered lakeside retreats was shattered last month when suspected drug-gang hitmen kidnapped a group of Mexican locals and dumped 18 decapitated bodies in two vehicles just miles (kilometers) from the lakeside tourist enclave of Ajijic. The explosion of violence followed months of escalating tension in a turf war between the Sinaloa and Zetas drug cartels that has spread from smuggling routes in the north to the fringes of Mexico's second biggest city, Guadalajara. Just 40 minutes from the Jalisco state capital, the Chapala slayings horrified foreigners and locals alike, who locked themselves indoors and stopped going out. "We thought it was going to be the end of Ajijic," said Phil Rylett, a 61-year-old retiree from Sacramento, California, who was in the picturesque village finalizing plans to buy a house with his wife. "You can't live in paradise if you're afraid." Cross-border tourism to Mexico has been a notable victim of the drug war, which has killed more than 55000 people since President Felipe Calderon launched an army-led offensive against the cartels shortly after taking office in December 2006. The number of day trippers to Mexico fell by a quarter between 2008 and 2011 and the numbers of US tourists staying also declined ...