Three teenage boys who spent a night lost in an abandoned mine in Dodge County, Wisconsin won't face trespassing charges, officials announced Thursday.

Dodge County Sheriff Dale Schmidt says the University of Wisconsin-Milwaukee, which owns the mine near Iron Ridge, decided not to press charges. Schmidt says university officials felt the boys had learned their lesson.

Tate Rose and Zachary Heron, both 16, and 15-year-old Samuel Lien decided to explore the mine on July 10, despite no trespassing signs. A large-scale search was launched after the boys were reported missing. More than 100 searchers from agencies around the state worked to find the boys.

Fox6Now.com reported that more than 100 searchers from agencies around the state worked to find the boys.

They were found unhurt the following day in the 4-mile-long maze of tunnels.

The Associated Press contributed to this report