Updated at 11:32 a.m. ETAuthorities have arrested a man in Washington state in connection with the appearance of a number of suspicious packages on Monday at federal facilities around Washington, D.C.The suspect was arrested around 12 hours after the first discovery of the packages, a law enforcement source told NPR. Law enforcement officials asked not to be identified discussing the case because the investigation continues.The man who was arrested has so far not been identified either and officials declined to provide more detail about him. The man was expected to appear in federal court for the western district of Washington state on Tuesday. Investigators are analyzing the packages discovered around the National Capital Region on Monday to determine whether any of them contained functioning explosive devices. The Associated Press reported that the packages "contained black powder along with rambling, nonsensical notes similar to those the man has been known to send in the past ... Authorities did not name the man, but said he was known to law enforcement."NBC News reports that one of the facilities targeted was the National Defense University at D.C.'s Fort McNair, which received a package at 8:30 Monday morning and evacuated the building. Officials at Fort McNair told the TV network that the package tested positive for explosive black powder. An X-ray examination showed what looked like some kind of Global Positioning System device and a fuse. The package was rendered safe.Two other packages were sent to sites at Virginia's Fort Belvoir, an Army base southwest of Washington, D.C. One of those packages contained a vial of liquid and a circuit board, and was also rendered safe, NBC reports.Other suspicious packages were found at D.C.'s Joint Base Anacostia-Bolling, mail processing facilities for both the CIA and the White House, and a naval base in Dahlgren, Va.No injuries or explosions were reported."We are tracking the delivery of suspicious packages to multiple military installations in the National Capital Region," Defense Department spokeswoman Lt. Col. Michelle Baldanza told CNN. "This incident is currently under investigation and we refer all queries to the Federal Bureau of Investigation." Copyright 2018 NPR. To see more, visit http://www.npr.org/.