A man accused of kidnapping his 7-year-old daughter and posing as a member of the Rockefeller clan may have planted false clues that he planned to flee the country in a yacht, authorities said Wednesday.

Clark Rockefeller, 48, was last seen at Grand Central Terminal on Sunday night, hours after he was accused of snatching his daughter Reigh during a supervised visit in Boston. Authorities said at the time they believed he may have been trying to flee to Bermuda or Peru on a yacht docked on Long Island.

Today, officials said it’s possible Mr. Rockefeller led people to believe he was heading for a Long Island marina in order to throw police off his trail. They aren’t even sure he owns a yacht.

“We have been unable to confirm that at this time,” a Boston Police spokesman, Eddy Chrispin, said of the boat.

The chief spokesman for the New York Police Department, Paul Browne, said investigators focused their search on marinas based on information obtained from witnesses, but still haven’t found any trace of Mr. Rockefeller or his daughter. “They had time to get away,” he said today.

Meanwhile, officials have been dealing with a flood of false leads. Investigators in New York followed up on a 911 call that the girl was seen on a bus in Brooklyn, but the tip didn’t pan out.

Police near Smyrna, Del., about three hours south of New York, said they received a report that the girl and her father were seen along Route 13 yesterday. Investigators canvassed the area and questioned drivers at rest stops, but didn’t find any sign of the two.

Mr. Chrispin said the last confirmed sighting was Sunday night at Grand Central.

In other developments, the Massachusetts woman who told police Mr. Rockefeller paid her $500 to drive him to New York City from Boston said she had no idea anything was amiss.

A family friend, Aileen Ang, told reporters that Mr. Rockefeller asked her to pick him up Sunday at the Boston Sailing Club. When she arrived, Ms. Ang said Mr. Rockefeller’s daughter, Reigh, was with him.

During the ride, Ms. Ang said the girl seemed happy, telling her father she loved him.

After she dropped them off, Ms. Ang said she learned an Amber Alert had been issued and immediately called police.

Mr. Rockefeller used at least four known aliases, and a spokesman for the Rockefellers has said there is no indication the fugitive is related to the famous family.