Cathy Huynh, left, and Kari Bowerman took this photo while backpacking in Vietnam. (CNN)
ROCHESTER, Minn. (AP) -- Family and friends of a Winona State University graduate who died in Vietnam under unexplained circumstances are launching a letter-writing campaign to get the U.S. government to seek answers.
Kari Bowerman, of Lake Geneva, Wis., and her friend, Cathy Huynh, of Hamilton, Ontario, became sick and died during a vacation trip. Their families have been unable to get an explanation from Vietnamese authorities or U.S. officials in Vietnam.
The Post-Bulletin of Rochester reports friends and family theorize they may have died of some type of insecticide poisoning.
Kari's sister, Ashley Bowerman, says their campaign has spread to at least 12 states. Minnesota Sens. Al Franken and Amy Klobuchar and Rep. Tim Walz are among the targets.
Franken says he's going to do what he can to get answers.
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