Calling themselves "Shinobi warriors," the men carried knives, throwing stars, swords, nunchucks and a bow and arrows.
Tadeusz Tertkiewicz, 20, and Jesse Trojaniak, 19, were each charged with weapons possession. Tertkiewicz is also charged with harassment for a letter left for an ex-girlfriend.
The letters warned drug users and drug dealers that the "Shinobi will stop your cruel and sadistic intentions with justified yet, merciful force."
In the letter, the two men accused drug dealers and users of having "committed sin of passing impurity" to others and that the "wind guides us to those of impure heart and intent."
"Their intentions may have been good, but we tell everyone that they shouldn't take the law into their own hands because it will cause more problems for everyone in the long run," Detective Capt. Robert Rowan said.
Trojaniak's father told The Associated Press his son is "not a maniac" and was only trying to
help a friend.