The incident took place in Hartford County at Southington High School early Thursday, Oct. 26 in Southington.
According to Lt. Keith Egan of the Southington Police, the school received a call with a threat of gun violence inside the school. The call originated from an out-of-state number.
"After working with state and federal officials, it has been determined that the threat was unsubstantiated," Egan said.
The high school will resume normal operations with an added police presence to remain on campus for the remainder of the day.
Additionally, there will be an added police presence at all other schools townwide for the rest of the day.
"We will continue to work with state and federal officials to investigate this matter further and, if possible, prosecute to the fullest extent," Egan added.
Click here to follow Daily Voice Stamford and receive free news updates.