"There is substantial evidence that some of these fires are caused by people who have crossed our border illegally," McCain, said at a press conference Saturday after touring the Wallow fire, which began on May 29 and has burned over 500,000 acres to date.

“They have set fires because they signal others, they have set fires to keep warm, and they have set fires in order to divert law enforcement agents and agencies from them,” McCain said. “The answer to that part of the problem is to get a secure border."