CLIFTON, N.J. -- Police arrested two men dressed like ninjas and armed with Asian martial arts weapons who said they were delivering warning letters to drug dealers and users.

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...