(CNN) -- Brendan McDonough, a lookout for his elite 20-man Arizona wildfire-fighting crew, saw Sunday's blaze change directions and warned his team by radio from his hilltop perch. The new conditions, he told them, also were forcing him to leave that spot, officials recalled Tuesday. He did as he was trained, officials said. And because he did, McDonough might have escaped his own death by seconds. McDonough was trying to go to another lookout point when the Yarnell Hill fire killed 19 members of Prescott Fire Department's Granite Mountain Hotshots, Prescott Fire Department spokesman Wade Ward said. The incident, part of a fire that has burned more than 8,400 acres since Friday, produced the deadliest day for firefighters since the 9/11 attacks.
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NEW: Lookout warned his team, then left post as prescribed, officials say
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NEW: The lookout, Brendan McDonough, departed hilltop post just before flames came
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19 members of a "hotshot" team from Prescott died in an Arizona wildfire Sunday
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McDonough was the only team member to survive
One Prescott official, speaking with @placeholder at the news conference in Prescott Tuesday, told reporters that it was protocol to have a hotshot lookout in place at all times.