The Washington, D.C. headquarters of the Republican National Committee was cordoned off Wednesday morning after someone sent vials of blood into the building. Three sources familiar with the situation told NBC News.
Capitol police responded to the scene at 7:45 a.m. following a report of a suspicious package, police said.
The package contained two vials of blood and was cleared by the Emergency Response Unit, police told NBC News. The source of the packet and its contents are investigated.
It is not clear if the suspect is in custody.
The road to the RNC headquarters has reopened to traffic and Capitol Police have left the scene.
This is a breaking news story. Please check for updates.