Around 0430 Engine 9 was dispatched to a backfill assignment at Suffolk Station 1, while the downtown companies were operating on a second alarm.  Engine 9 went enroute with a crew of four while another crew was left in quarters to staff the second engine.  While enroute command requested the third alarm which prompted Engine 9 to the scene.  On arrival we laid in our own supply line and set up the deluge gun to operate on the bravo exposure.  We were later repositioned to operate a handline from division 3 of a neighboring building onto the b exposure, and finally to overhaul in the exposure building until crews were pulled for structural integrity concerns.  After picking up (thanks to E10's crew for the help) we cleared and headed back to the village.