US Capitol Police officers in riot gear have clashed with dozens of demonstrators who gathered outside the Democratic National Committee (DNC) headquarters in Washington to demand a ceasefire in Gaza, Reuters reports.

The protest was organised by three advocacy groups and held in an area near the US Capitol. Lawmakers who were inside the DNC building said police had evacuated them from the area.

Protesters linked arms in front of the DNC building’s entrance, where some sang: “Which side are you on?” Officers pushed and pulled the protesters to try to remove them from the area, at one point shoving one protester down a staircase leading to the entrance.

Police also used pepper spray and fired projectiles containing chemical irritants.

US Capitol Police said approximately 150 people were “illegally and violently protesting”. It said six officers were treated for injuries, ranging from cuts to being pepper sprayed and punched.