In 2011, 120 Americans were killed in Mexico, up from 35 in 2007, The Houston Chronicle reported Sunday.
In most instances, the U.S. citizens were mistakenly killed by drug cartel members, said Hugo Rodriguez, head of the U.S. State Department's citizens services section for the Americas.
Mexican gangsters aren't "going after Americans specifically in any way, either tourists or people involved in that business," Rodriguez said.
Most of the murders were along the U.S.-Mexico border and a significant number occurred in previously peaceful areas, officials said.
"We all know this is a gang problem. We have no connection with drugs," said Lorraine Kulig, who is originally from Houston, but now resides in the small Mexican city of Chapala. "But we can be caught in the crossfire."
The State Department in February advised U.S. citizens to avoid 14 of Mexico's 32 states and to use extreme caution when visiting four others.
The risk of Americans being targeted for violence remains relatively low
An estimated 19.9 million Americans visited Mexico in 2011 and about 1 million reside in the country, the department said. More than 50,000 Mexicans are killed in Mexico every year, authorities say.