BROOKLYN, Iowa — A Mexican man charged with killing an Iowa college student worked on a dairy farm for years under a false name just a few miles from where the young woman was allegedly abducted while running last month, his employer said Wednesday.

Cristhian Bahena Rivera was a good employee who showed up on time to take care of the cows and got along well with his co-workers, said Dane Lang, manager of Yarrabee Farms. The 24-year-old kept coming to work after Mollie Tibbetts disappeared July 18, and “nobody saw a difference” in his demeanor, Lang said.

When Rivera was hired in 2014, he presented an out-of-state government-issued photo identification and a matching Social Security card, he said. That information was run through the Social Security Administration’s employment-verification system and checked out, he said.

Rivera’s defense attorney, Allan Richards, acknowledged Wednesday that his client received his paycheck under a different name and that he was uncertain of his immigration status.