VIDEO: For the third time in less than a week, Phoenix Firefighters battled yet another fire at a recycling facility Thursday afternoon, sending plumes of heavy black smoke into the air west of downtown. The two-alarm fire started near McDowell and 20th Avenue at Liberty Iron and Metal. About 60 firefighters worked quickly to douse the flames coming from vast piles of recycling debris as workers at the facility used giant hooks to expose hot spots inside the stacks. Phoenix Fire spokesman David Ramirez says there were no injuries due to the fire. Because of the summer heat, firefighters must call in additional crews to rotate frequently to keep firefighters from becoming overcome by the heat, fire officials say. The cause of the fire is not yet known.