WAUKEGAN, Ill. (CBS) — A north suburban school bus driver has been arrested for sexual assault and abuse of an underage girl, after the victim’s mother found messages describing their encounters.

Kristin Miks, 33, of far north suburban Wildwood, was arrested Monday, charged with two counts of criminal sexual assault, and four counts of aggravated criminal sexual abuse, according to the Lake County Sheriff’s office. Her bond was later set at $150,000, and she was due back in court on June 12.

Police said the victim was 15 at the time of the alleged abuse.

Her mother found messages from Miks referring to her encounters with the girl, and called police.

Miks, a school bus driver for Woodland Community Consolidated School District 50, was suspended last month when the district was notified of a criminal investigation.

Police said the victim is not associated with the school district, and that she and Miks do not know each other through Miks’ job as a school bus driver. None of the encounters happened on the school bus.

“The sheriff’s office has assured the district that there is no reason to believe there is any connection with the district, or with Ms. Miks’ former bus duties, or the children she served,” said District 50 Superintendent Dr. Joy Swoboda.

Swoboda said emails have been sent to parents in the district, notifying them of the charges against Miks. She said letters also will be sent in the mail

The administration has recommended Miks be fired, Swoboda added.

The sexual assault charges are not the only legal problems Miks is facing.

A month ago, she was charged with animal cruelty, after authorities allegedly found three dogs in her home, all near death without food or water. She is due in court on June 10 on animal cruelty charges.

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