Oakland County Sheriff Michael Bouchard spoke on an arrest and investigation into an alleged mass shooting plot at a graduation for a high school in Pontiac earlier this week. Rep. Madeleine Dean ...

WATCH: Oakland County sheriff speaks on arrest in alleged mass shooting plot at graduation ceremony. Oakland County sheriff speaks on arrest in alleged mass shooting plot at high school graduation.

A 19-year-old was arrested and a 20-year-old is being sought in connection to an allegedly planned mass shooting at a Pontiac high school graduation.

DETROIT — A 19-year-old man was arrested after spending months planning an attack against a U.S. Army site in suburban Detroit on behalf of the Islamic State group, authorities said Wednesday.

An Oregon teen has been arrested in connection with an alleged mass shooting plot targeting the Three Rivers Mall in Kelso, in southwestern Washington, officials said.

(CNN) — An Oregon teen has been arrested in connection with an alleged mass shooting plot targeting the Three Rivers Mall in Kelso, in southwestern Washington, officials said. The suspect, whose ...

An Oregon teen has been arrested in connection with an alleged mass shooting plot targeting the Three Rivers Mall in Kelso, in southwestern Washington, officials said.The suspect, whose identity ...

An Oregon teen has been arrested in connection with an alleged mass shooting plot targeting the Three Rivers Mall in Kelso, in southwestern Washington, officials said.The suspect, whose identity ...

KELSO, Wash. — An Oregon teen has been arrested in connection with an alleged mass shooting plot targeting the Three Rivers Mall in Kelso, in southwestern Washington, officials said.