A 72-year-old Strasburg man died Wednesday as a result of injuries he sustained in an early morning fire that appears to have started as he was smoking while using an oxygen tank, investigators said. An alarm call at 5:35 a.m. from a sprinkler system activation alerted first responders to the fire at Massanutten Manor at 100 Massanutten Manor Circle in Strasburg. Strasburg firefighters were the first to arrive at the scene but many departments soon joined them. Shenandoah County Fire Marshal David Ferguson said the deceased man suffered from numerous medical issues and had just been released from an area hospital the day before the fire. The Fire Marshal’s Office has ruled the fire accidental, Ferguson said.