Police believe 12-year-old Joel Strother II and 10-year-old Carter Strother III may have been taken out of state against their will.
In a post on the department's Facebook page, Presque Isle police say they have had a phone conversation with boys' father, Joel Strother, who they say isn't cooperating.
Photos of the boys' dad were posted by police, who noted the birthmark on the left side of his neck.
Authorities say they have received tips from all over the East Coast.
Police think the missing kids may be traveling in a metallic-colored GMC Terrain, possibly with temporary paper plates, or a tan Cadillac Escalade.
Anyone with information is asked to call Presque Isle police at 764-4476.