MIAMI -- Authorities in Florida have arrested a 20-year-old former Oregon student with a weapons cache that included four AK-47s.

They say he had threatened over the Internet to carry out a Virginia Tech-style massacre.

KGW photo

Police shared these photos of part of the weapons cache.

The threat was discovered last month by authorities in Oregon, where Calin Chi Wong had attended high school and college

Two days later, the home he shares with his parents in Homestead, Florida, was searched and police say weapons were found stacked on shelves in plain view.

There were 13 firearms in all and more than 5,000 rounds of ammunition. Police say some of it could pierce armor and was meant "to take down aircraft or military machinery."

Wong has been charged with making written threats to kill or do bodily injury via the computer.