The death toll in an explosion and fire apparently caused by a gas leak at a refinery in Venezuela rose to 41, with more than 80 people injured, officials said. Eighteen members of the National Guard were among the dead, Vice President Elias Jaua said. About 209 homes and 11 businesses were damaged, Jaua said. President Hugo Chavez visited the site and declared three days of mourning, CNN reported. Most of the victims, including members of the families of the guardsmen who died, lived at a nearby military complex for the 45th Detachment of the National Guard, the Latin American Herald Tribune reported. The base received \"severe damage\" from the explosion, said Oil and Mining Minister Rafael Ramirez. Gas-leak alarms designed to alert communities surrounding the oil refinery never went off, a former pipeline maintenance contractor at the plant told The Wall Street Journal. \"We could smell the propane -- and I knew it was propane because it\'s what we use for cooking -- 40 minutes before the explosion,\" said Angel Mora. \"It was so strong we had trouble breathing.\" Refinery manager Jesus Luongo denied a lack of maintenance was a factor in the disaster.