French au­thor­i­ties or­dered near­ly 4,000 more peo­ple to evac­u­ate from At­lantic coast tourist sites Tues­day as re­turn­ing heat threat­ened fire­fight­ers’ frag­ile hold on a vast wild­fire west of Bor­deaux, widen­ing what may be France’s largest peace­time evac­u­a­tion.

Fire crews held the blaze in the Gironde re­gion in check through a calm night, bring­ing flare-ups near coastal dunes un­der con­trol and keep­ing the burned area un­changed at 420 square kilo­me­tres (162 square miles). Au­thor­i­ties called the fire sta­bi­lized, but not con­tained, and said it was still ca­pa­ble of break­ing loose as tem­per­a­tures rose and hu­mid­i­ty fell.

Fresh flames erupt­ed lat­er Tues­day near Grand Cro­hot, a pop­u­lar va­ca­tion beach on the Lège-Cap-Fer­ret penin­su­la, lo­cal au­thor­i­ties said. Fire­fight­ers backed by wa­ter-drop­ping air­craft bat­tled the re­newed flames to keep them from spread­ing.