WASHINGTON (Reuters) -A possible active shooter was reported at the U.S. Capitol on Wednesday, the Capitol Police said, urging people inside Senate office buildings to shelter in place.

The U.S. Senate was in summer recess and the majority of lawmakers were not in, but most offices retain a skeleton staff on site. There also are typically are dozens of workers staffing Senate cafeterias and coffee shops, security posts and working on building maintenance.

"If you are inside the Senate Buildings, everyone inside should be sheltering in place as the report was for a possible active shooter. It should be noted that we do not have any confirmed reports of gunshots," the U.S. Capitol Police said in a post on social media.

Police said they responded to an emergency call.

An advisory from the Capitol Police urged people to move inside their offices and take emergency equipment. It also asked them to silence their electronic equipment and remain quiet.

There was a heavy police presence outside the buildings, with some staffers standing outside and tourists gathered around the perimeters of the Capitol complex.

(Reporting by Moira Warburton, Patricia Zengerle, Kanishka Singh; Editing by Doina Chiacu)