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.

A Columbia County teen planned to set off an explosive at the mall in Kelso off I-5 and then shoot people as they fled the movie theater there, the FBI said.

The suspect arrested after allegedly planning an elaborate mass shooting attack at Three Rivers Mall in Kelso, Wash., has been identified as a 14-year-old boy.