Frontline escalation in Yemen war tests months-long calm

A flare-up of fighting in Yemen’s energy-rich Marib province is testing 10 months of relative calm, the longest stretch in an eight-year civil war, under a U.N.-brokered truce deal that lapsed in October but had largely held.
Forces of the Iran-aligned Houthi movement, de facto authorities in northern Yemen, launched an attack late on Tuesday into Marib’s Harib district.
There was an unknown number of casualties in the clashes.
Marib, which lies around 120 km east of the capital Sanaa, had been the main frontline before the truce was first agreed last April, as forces of a Saudi-led military coalition repelled advances by the Houthi movement bent on seizing full control of the province in central Yemen.
Yemen has been mired in violence since the Houthis ousted the government from Sanaa in late 2014, prompting the Saudi-led coalition to intervene months later.