A woman in the United States has been charged with murdering her husband and trying to pass his death off as a suicide.

29-year-old Texas nurse Tu Thien Huynh called police claiming her 34-year-old husband Steven Hafer had shot himself in their bedroom.

According to a press release from the Houston Police Department, officers found suspicious evidence that led them to believe Huynh killed her husband.

During her preliminary court hearing last Monday, prosecutors said the shotgun used in the shooting had been wiped clean and the trajectory of the bullet did not match a self-inflicted wound, reported Houston Chronicle.

Investigators also said Huynh kept changing her story about the fatal incident and later admitted to having an affair with an ex-boyfriend.

Huynh, originally from Vietnam, moved to the United States in 2004 and later gained citizenship, according to the district attorney’s office.

She married Hafer in 2014 and had a daughter just over two years ago.

In court, State District Judge Randy Roll ruled that Huynh must surrender her passport if she makes her $US50,000 bail.

– with other agencies