Ten Granite City High School students were suspended earlier this week as a result of inappropriate comments posted on the social media site Twitter including a threat to the school, according to district officials.
"We treat all threats very seriously," said Granite City School District Superintendent Harry Briggs, who would not provide specifics about the threat. "We are continuing to investigate that part of it."
The students' suspensions varied from five to 10 days, according to Briggs.
Briggs said school officials occasionally monitor Twitter, especially when "someone indicates there might be something inappropriate going on."
The tweets that resulted in students' suspensions were posted during school hours.
Granite City High students are permitted to have cellphones in school.