At 0214 Holbrook was activated for a smoke condition at 137 Fairfield Drive located in the Colony Complex. Upon arrival Chief Reimo observed active fire from the rear roof of the residence and immediately transmitted a working structure fire. This transmission initiated the automatic mutual aid response plan. An aggressive interior attack lead by Chief Apostol was made through the garage attic access to the actual origin of the fire which was possibly caused by a lightning strike. Fire was extinguished and overhaul conducted with no reported injuries to any household or fire member.