WATERFORD TOWNSHIP, Mich. -

Michigan State Police tests have determined that heroin was in a syringe that jabbed a woman while she shopped at a Walmart store in Waterford Township.

More: Woman stuck with syringe at Walmart

The incident occurred in March. The 46-year-old woman from Rochester Hills was trying on a pair of pants when she felt a jab in her leg.

She found the syringe inside the pants and turned it over to police.

Tests have now confirmed that traces of heroin were in the syringe.

The woman received a tetanus shot.

Police continue to investigate to learn where that syringe came from.