A teenage student at a southern Utah high school has been charged with bringing a homemade bomb to the school that was discovered in a backpack emitting smoke and prompted an evacuation, police said Tuesday.

The boy was arrested Monday night after Pine View High School in the city of St. George was evacuated for two hours that afternoon while the FBI and a bomb squad investigated. Police declined to identify the arrested teen or give his age, reports NBC News.

Authorities said additional charges also are pending against the teen as a suspect in the raising of the Islamic State group's flag on a pole at another Utah high school last month just after the Florida mass school shooting that was followed by numerous other threats to schools around the U.S.

No one was hurt Monday after the backpack was found in a common area of the school by a student who reported it to a teacher.

The boy was arrested and booked into a detention center on charges of manufacture, possession, sale, use or attempted use of a weapon of mass destruction, St. George police said in a statement.

"Based on our investigation we can confirm this was a failed attempt to detonate a homemade explosive at the school. It was also determined that the male had been researching information and expressing interest in ISIS and promoting the organization," police said.