He was picked up late Saturday afternoon at an apartment in the Mount Vernon neighborhood north of downtown, Baltimore Police spokesman Sterling Clifford said.
The 48-year-old father is accused of making elaborate plans to take his daughter by fleeing a social worker during a supervised visit last weekend and setting up two drivers to take them to New York City. They were last seen at Grand Central Terminal in New York on Sunday night.
Police initially suspected Rockefeller was trying to flee to Bermuda or Peru on a yacht docked in Long Island. But authorities later believed Rockefeller may have planted false clues to throw investigators off his trail.
Boston police refused to comment before a news conference scheduled for 6 p.m.
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