Heidi Schmidt | Evanston police(EVANSTON) A Humboldt Park woman has been charged with setting off a minor explosion inside the bathroom of a Target store Wednesday afternoon in north suburban Evanston.

Heidi Schmidt, 44, was charged with one felony count each of aggravated arson and unlawful possession of an explosive or incendiary device, Evanston police announced Saturday. She lives in the 4000 block of West Crystal in Chicago.

Emergency crews were called at 4:08 p.m. Wednesday to the store at 2209 Howard St. following the explosion involving a plastic bottle inside the women’s bathroom, police said.

Damage was limited to one bathroom stall, police said. No one was hurt.

The Cook County sheriff’s bomb squad cleared the scene. No threats or suspicious activity were reported at the store before or since the explosion, and the store stayed open for business, police said.

In addition to the plastic bottle, investigators found items commonly used to produce a chemical high. During the mixture process, these items can become volatile and explode, police said.

Police said “there is no indication that the incident is related to any policies that the Target store has in place.”

Schmidt’s bond court date was not immediately available.