The U.S. Transportation Department has fined AirTran Airways $60,000 for violating a federal rule that prohibits advertising fares without clearly disclosing additional fees and taxes.

Under federal rules, airlines that advertise airfares in the U.S. can disclose government-imposed taxes and fees separately on the same page or an Internet link so long as it is easy for passengers determine the full price.

An investigation by Transportation Department found that AirTran advertised $59 one-way fares last fall on several websites. But the ads did not disclose the types or amounts of taxes and fees until consumers clicked on the ads and scrolled to the fine print at the bottom of the subsequent page.

“We will continue to take enforcement action when our airline price advertising rules are violated,” Transportation Secretary Ray LaHood said.

AirTran is a subsidiary of Southwest Airlines, which is expected to absorb the company completely later this year.

Under a recently adopted federal rule, U.S. airlines will be required to add all government taxes and fees into the total advertised fare starting Jan. 26.

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