BERLIN (AP) – A woman in Germany died from a head injury as she stood outside her house on New Year’s Eve to watch fireworks and an autopsy suggests it was a gunshot wound, authorities said Thursday.

Police in the northern city of Kiel said the 39-year-old mother of three had stepped out of her house in the nearby town of Schoenberg to watch fireworks shortly before midnight. A few minutes later, she collapsed with a bleeding head wound. She died at a hospital in Kiel, where doctors found small metal splinters in her head.

Prosecutor Birgit Hess told the German news agency dpa that “after the autopsy, we believe with a high degree of probability that the woman was killed by a gunshot wound.”

Authorities initially suspected that an illegal firework might be to blame. Germans typically welcome the new year by setting off large quantities of fireworks.