Ammar Abdulmajid-Mohamed Said allegedly engaged in detailed attack planning to carry out a mass shooting at the U.S. Army's Tank-Automotive & Armaments Command facility.

The suspect sought to use a drone, Molotov cocktails and armor-piercing ammunition to attack a base outside Detroit on Tuesday, the authorities said.

Former National Guardsman allegedly planned mass shooting at Detroit Arsenal, provided tactical support to undercover agents posing as ISIS operatives.