Washington (CNN) -- Law enforcement officials briefly evacuated the area around the House of Representatives chamber on Monday after the discovery of a powdery substance, according to a spokeswoman for the Capitol Hill police.
The area evacuated included both the House press galleries and the galleries used by tourists to watch congressional floor deliberations.
The galleries were evacuated out of "an abundance of caution" while authorities investigated the incident, spokeswoman Kimberly Schneider said.
Capitol Hill police later confirmed, however, that authorities had deemed the area safe, and that both congressional staff and members of the media had been allowed to return.
The House is scheduled to return from its summer recess at 2 p.m. on Tuesday
CNN's Deirdre Walsh contributed to this report