HOFFMAN ESTATES, Ill. — Three students were arrested Friday at Hoffman Estates High School after a gun was found in a backpack.

At around 7:40 a.m., a school resource officer responded to an altercation between three juveniles. They were all placed into custody by the resource officer, police said.

It was determined by authorities that a backpack that belonged to one of the juveniles contained a 9 mm hand gun. The school was placed into a soft lockdown for a short period of time to allow authorities to investigate.

An undetermined amount of ammunition was also found. At this time, it is unknown if the gun was loaded.

Police determined that there were no other active threats to the school.

Two of the juveniles were charged with disorderly conduct and the juvenile who allegedly had the gun was charged with unlawful possession of a weapon on school grounds, unlawful possession of ammunition and disorderly conduct.