BREAKING: Suspicious Substance at the Senate

Just a few minutes ago, a tipster emailed us:

Left work today (Hart Office Building in the Senate) and we discovered the northwest door of the Dirksen building was blocked off as haz mat teams, police, and the fire department mysteriously responded to something. The Capitol Police told us it wasn’t a drill, but declined to say more.

We thought we had a mini-scoop on our hands; but it looks like the AP is already on the scene:

Police closed off entries and exits at the Senate’s Dirksen Office Building on Monday and announced that people should avoid the building’s basement. Capitol Police Sgt. Kimberly Schneider said an alarm went off about 4:50 p.m. indicating a suspicious substance near a basement post office facility.

This will probably turn out to be nothing; but if it turns into something, we’ll update you.

Exits sealed at Senate office building [AP]