Dozens of Washington, D.C., police in riot gear and on horseback converged on one of the last remaining Occupy encampments in the U.S. on Saturday, clearing the grounds of tents that they said were banned under park rules.

The move left large swaths of open space and raised questions about exactly what would remain of the encampment once the enforcement was over.

Police said they were not evicting the protesters. Those whose tents conformed to regulations were allowed to stay, and protesters remain able to demonstrate on the site at all hours provided they don't camp there.

Dozens have been camped since October 1 in McPherson Square, just blocks from the White House. Similar to the New York protesters, who strategically occupied a park near Wall Street to highlight their campaign against economic inequalities, the District of Columbia group selected a space along Washington's K Street – home to some of the nation's most powerful lobbying firms.

On Saturday, the police used barricades to cordon off sections of McPherson Square, a park under federal jurisdiction, checked tents for mattresses and sleeping bags, and sifted through piles of garbage and other belongings. Some wore yellow and white biohazard suits to guard against diseases identified at the site in recent weeks.