A wild fire starting Thursday in the southern town of Gironde was finally put under control early Friday after destroying about 550 hectares of forest, local media reported. However, some 200 firefighters working in the area remained on alert during the day in case the fire flares up again due to heat wave. \"Our point of vigilance is that the wind that was again blowing would not relight the fire and propagate it,\" Gironde Prefect Phillipe Stefanini was quoted by BFMTV news channel as saying. No heavy casualty was reported except a serious injury of one firefighter. The cause of the fire is still under investigation.