An explosion at a gender-reveal party in Iowa fatally wounded a woman, authorities said.

The Marion County Sheriff’s Office said a 56-year-old woman was killed Saturday during a party in Knoxville to announce the gender of an expectant couple’s baby.

The planned announcement created an explosion, and a flying piece of debris struck the victim, authorities said.

Officers responded around 4 p.m. and pronounced the woman dead at the scene.

The Bureau of Alcohol, Tobacco, Firearms and Explosives is involved in the investigation, news station WBNS reported.

No other details were released about the fatal incident. The identity of the woman hasn’t been revealed.

With Post wires