SAUGUS – Firefighters battled an afternoon brush fire Friday off Auburn Street wrapping up one of the driest weeks on record.Fire Chief James Blanchard said Thursday the burn index was the highest it had been in some time and conditions were the worst possible for a fire.Auburn Street resident Ray Lawrence said he was home with his son when he thought he smelled smoke. Moving outside he said he looked down on the tracks and could see flames.Lawrence also said shortly before he spotted the flames he and several other neighbors heard an explosion. He also reported seeing a group of kids in the area who he didn’t recognize shortly before the fire broke out.”The smoke was brutal,” he said. “The area that burnt was not the usual area that burns.”Lawrence said it’s not unusual for the brush around the tracks to catch fire but it doesn’t usually burn on his side of the tracks.This time, however, Lawrence said the brush on the Auburn Street side of the tracks caught fire and burned steadily toward the small embankment leading to a row of homes. He said he has no doubt the home at the end of the line would have gone up if firefighters hadn’t responded as quickly as they did.