William Gomez, 57, and his grandchildren Marcos, 7, and Dominique, 8, have been missing since Sunday afternoon, when Gomez, who authorities say suffers from a brain tumor, took them a public park in the Dallas suburb of Carrollton, the Dallas Morning News reported.
Carrollton police spokeswoman Nicole Rodriguez said a trail of debit card activity shows Gomez is traveling in the direction of Chicago, noting his debit card account has been accessed in Little Rock, Ark.; Troy, Tenn.; Paducah, Ky., in Indiana and most recently in Chicago.
She added a bulletin has been sent to the National Center for Missing children, and a request has been sent to Chicago media to get photographs of the three on local television.
"We don't have any reason to believe the kids are not still with him, and not still OK. He's just driving," Rodriguez said.
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