ROYAL OAK, Mich. — Federal agents have raided the house of a high-ranking Department of Homeland Security official as part of an unspecified investigation, The Detroit News has learned. Neighbors and law enforcement officials confirmed the raid happened Friday at the home of Homeland Security Special Agent in Charge Vance Callender, who oversees operations in Michigan and Ohio. The search involved approximately 15 agents and lasted about six hours at a pea-green, Colonial-style home east of downtown Royal Oak, according to an eyewitness. News of the search has spread widely within the region’s…