UPDATE: 4/12/2013 – 4:18 p.m.

CHICAGO (CBS) — Two teenage boys have been arrested in Elgin, after a shotgun was found in a locker at Gifford Street High School on Thursday.

Two 15-year-old boys — one from Streamwood, the other from Elgin — both have been charged with three felonies: possession of a firearm by a gang member, unlawful use of a weapon with 1,000 feet of a a school and unlawful use of a weapon. They were being held at the Kane County Youth Home pending a detention hearing.

The boy from Streamwood was arrested Thursday. The boy from Elgin was arrested Friday.

Police learned one boy sold the gun to another on school grounds.

Police received a tip from another students that led authorities to search a locker at the school around 11:30 a.m. on Thursday.

Officers and school administrators locked down the school and searched the building, lockers and students.

It was during the search that police found an unloaded shotgun. No ammunition or other dangerous items were found during the search.

“I am proud of the student who brought this information forward. It is this type of brave action that leads to a safer community” said Elgin Police Chief Jeffrey Swoboda.

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