Lockdown at Republican National Committee Headquarters, D.C.

Update (0930 EST): U.S. Capitol Police have issued an all-clear following an investigation into a suspicious substance.

At approximately 0836 EST, initial reports indicated that a lockdown had been initiated at the Republic Party National Committee (RNC) Headquarters in Washington D.C.

By 0840 EST, local media confirmed that a suspicious package had prompted a HAZMAT response by emergency services. The lockdown is currently still in effect.

Several road closures have been declared near the headquarters and a large police presence has been noted.

This is developing.