The FBI has taken samples from the # ##box at Joint Base McGuire - Bolling . They now say there was no suspicious letter or letter . The screening equipment initially indicated there was a hazardous substance , an official says .
The FBI has taken samples from the mail facility at Joint Base Anacostia-Bolling . Authorities now say there was no suspicious package or letter . Mail screening equipment initially indicated there was a hazardous substance , an official says .