Yemeni security officials say at least 52 people have been killed and 25 injured in two days of fighting in central Yemen between rebels and forces loyal to the internationally recognized government.

The officials said Sunday government-allied forces have taken control of several areas previously controlled by the rebels, known as the Houthis, between the central provinces of Marib and Shabwa. The officials spoke on condition of anonymity because they weren't authorized to brief journalists.

A truce between the warring parties that began April 10 has largely held despite violations by both sides. The fighting in Yemen pits Shiite Houthi rebels and supporters of a former president against Yemen's internationally recognized government, supported by a Saudi-led, U.S.-backed coalition.