Suspicious packages have been sent to six government and military sites around the US capital Washington, according to media reports Monday.
"On March 26, the Federal Bureau of Investigation responded to multiple government facilities for the reports of suspicious packages".
On Monday, three military basesconfirmed receiving packages containing explosive materials, but all packages were detected before they could be opened. The parcel tested positive for black powder, a substance found in explosive devices, and an X-ray scan appeared to show a Global Positioning System locator and fuse attachment.
The package sent to McNair in D.C. tested positive for black powder and, according to CBS, had a fuse.
The building was evacuated and later cleared around 1:15pm.
During screening, the packages were found to be suspicious, although it is unclear what made them suspicious.
Williams said some of the packages were accompanied by what investigators told him were "rambling and disturbing" notes, and at least two of them had explosive material in them.
Authorities did not immediately name the man but said he was known to law enforcement.
Parcels arrived to two sites at Fort Belvoir in Virginia in the afternoon, addressed to The National Geospatial-Intelligence Agency and the defense university. Court documents are expected to give insight into how many packages were mailed and whether or not the devices were actually explosive.
"We are tracking the delivery of suspicious packages to multiple military installations in the National Capital Region".
Defense Department spokeswoman Lt. Col. Michelle Baldanza said they are aware of the situation and it is being investigated.
The FBI takes all suspicious packages seriously and has been coordinating with our local, state, and federal partners on established protocols of how to handle suspicious packages.