MIAMI (AP) — A 20-year-old with a weapons cache that included four AK-47s was arrested after threatening over the Internet to undertake a Virginia Tech-style massacre, authorities said Thursday.

Oregon authorities learned of a March 25 Internet message allegedly posted by Calin Chi Wong in which he threatened to re-enact the Virginia Tech killings. Two days later, Homestead Police searched the home Wong shares with his parents and found the weapons in stacked on shelves in plain view, police said.

Wong had 13 firearms in all, more than 5,000 rounds of ammunition, some that could pierce armor, and 100 rounds in a feeding clip.