Richard Evanchec, FBI Pittsburgh special agent in charge, outlines the police investigation against a Valencia man charged with plotting acts of terrorism on behalf of ISIS at a press conference Tuesday, Sept. 15 in Pittsburgh.

PITTSBURGH -- At a news conference Tuesday, Sept. 15, U.S. Attorney Troy Rivetti of the Western District of Pennsylvania said a Valencia man alleged to be plotting a terrorist attack was arrested in a covert investigation by the FBI after “disturbing developments that unfolded quickly” over the past weekend.

Jonathan Hunter Kramer, 21, was arrested Saturday, Sept. 12. He is accused in a federal complaint of obtaining a semiautomatic rifle, large amounts of ammunition and other weapons -- “knowing, and having reason to believe, the firearm and ammunition would be used to commit the federal crime of terrorism,” Rivetti said.

Richard Evanchec, FBI Pittsburgh special agent in charge, said Tuesday morning that law enforcement “successfully disrupted what we assessed to be an imminent threat of violence, inspired by ISIS.”

“The defendant, Jonathan Hunter Kramer, was taken into federal custody after a coordinated investigation and search arrest operations that occurred Saturday, Sept 12,” Evanchec said.

“Jonathan Kramer demonstrated a sustained devotion to the Islamic State of Syria. He recorded a pledge of allegiance to the same. Following that pledge, he made efforts to spread their propaganda, and shared ways to kill, all in the name of a foreign terrorist organization.”

This is a developing news story.