By the time of his capture, Guzman's empire stretched from Canada through Latin America, Europe, parts of Asia and Australia. He is believed to have amassed a fortune worth billions.
U.S. and Mexican authorities were close to nabbing Guzman in the past but arrived at resorts or other locations hours or days too late, the law enforcement official said. They were never closer than in recent weeks.
Last week, Guzman's pursuers were on his heels during raids at the stash houses in Culiacan. The law enforcement official said Guzman was believed to be just ahead of Mexican troops when he vanished in the underground network below the houses before absconding to the high-rise condo in Mazatlan, along the coast.
Associated Press writer Eileen Sullivan contributed to this report.
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