Houthi fighters opened fire on protesters in the central Yemeni city of Ibb on Saturday, killing one person and wounding another, local sources said.
The crowd had gathered in a square after a new power-sharing deal was reached on Friday to demonstrate against the Houthis' role in overturning the government last month.
Following the shooting, thousands more people took to the streets in protest. Witnesses said the Houthis were deploying more security forces in response.