An 80-year-old man injured in an explosion at his St. Paul home last month has died. A spokeswoman for Regions Hospital in St. Paul tells the Star Tribune that John Lundahl died Tuesday at the hospital from his injuries. The Nov. 23 explosion left Lundahl with significant burns and a broken arm and pelvis. Lundahl was found buried beneath insulation and debris. Firefighters pulled him out of the ruins. Several nearby buildings were condemned because of damage caused by the explosion. A gas leak is suspected, but fire officials say the cause remains under investigation.