Yemen war: mass displacement fears as fighting intensifies in Marib

Development threatens to exacerbate what is already the world's worst humanitarian crisis

Residents in the Yemeni province of Marib are bracing for what could be the worst mass displacement of the war as a Houthi rebel offensive intensifies, leaving more than 2 million people trapped.

Marib, which is controlled by parties loyal to the Yemeni government, has faced intermittent attacks from rebel forces over the last year as the Houthis have steadily gained ground in the area. A renewed assault since last month, however, has quickly morphed into one of the most ferocious battles of the seven-year-old war.