(CNN) While students in a South Carolina school participated in the National School Walkout this week, a custodian helped herself to their cash, police said.

The incident occurred at Richland Northeast High School on Wednesday.

Aisha Evans, a custodian at the school, went into a classroom while students were outside and rummaged through three book bags, the Richland County Sheriff's Department said.

In all, Evans stole $180, the department said.

The custodian was arrested soon afterward and charged with three counts of petty larceny.

Evans, 32, was employed by Service Solutions, an agency that provides custodial services to the district's school.

The agency terminated the woman, the school district told CNN affiliate WIS.

"On Thursday, March 15, Service Solutions notified Richland Two that Evans is no longer an employee of the company and was informed that she cannot come on any Richland Two property," Richland Two School District said in its statement to the affiliate.

It's unclear whether Evans has retained a lawyer.