NEW YORK (CBSNewYork/AP) — Sen. Charles Schumer is calling for a federal investigation of airlines who won’t allow their fares to show up on third-party websites such as Expedia, Orbitz and Travelocity.

The New York Democrat said Sunday that the practice prevents consumers from seeing all their options when booking a fight.

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The Justice Department is already investigating possible collusion among major airlines to limit the number of available seats to keep fares high. Schumer says the investigation should be expanded to look at how airlines restrict access to their fares on third-party sites.

He said Southwest and Lufthansa airlines are already restricting data.

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Schumer said the airlines appear to be trying to drive consumers to their own websites, but he said that limits competition and makes it harder for consumers to find the best deal on a flight.

The practice also threatens the future of sites such as Expedia, Orbitz and Travelocity, the senator said.

“We do nothing, they might be gone in a year or two,” Schumer told reporters, including WCBS 880’s Jim Smith and 1010 WINS’ Roger Stern. “And this great innovation of technology, which is so needed, which is so helpful, could be gone.”

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