Firefighters last night were battling a large blaze that broke out earlier in the day on one of the few remaining expanses of pristine forestland in the northern prefecture of Halkidiki. The blaze started near a ravine in Sithonia, the middle prong of the Halkidiki peninsula and by far the least developed. Fanned by strong winds in the area, the blaze spread quickly but had not approached any built-up areas by the late evening. Four firefighting planes and two helicopters aided firemen on the ground but their efforts were hampered by rough terrain and strong winds. As for the cause of the fire, suspicions of arson had not been confirmed by late yesterday. Local firefighters did not rule out the possibility that the blaze was sparked by a bolt of lightning, the cause of around 30 fires in the past two weeks. Another large fire that broke out in forestland in the Cretan prefecture of Rethymno yesterday had been extinguished by late last night.