BERLIN, Sept. 18 (Xinhua) -- The Federal Cartel Office in Germany will continue with antitrust probe into the development of airline tickets in the country centered on market leader Lufthansa, the Bonn-based agency announced on Tuesday.

Speaking at a travel trade fair in Cologne, Federal Cartel Office director Andreas Mundt highlighted that there were several connections where Lufthansa, the by far largest German carrier, had no significant competitors. "We cannot say that everything is in order in the German aviation market and we know that Lufthansa is still flying some routes as a monopolist," Mundt said.

The antitrust regulator is hereby responding to complaints filed in the wake of the bankruptcy of budget airline Air Berlin, large parts of which were subsequently integrated into the Lufthansa subsidiary Eurowings.

Back in May, the Federal Cartel Office said that it had identified a rise in ticket prices by 25 to 30 percent since the fall of 2017, but argued that this development in itself did not justify a formal lawsuit against Lufthansa for abuse of its monopoly position.

Lufthansa has in turn questioned the accuracy of data provided by the antitrust regulators with view to the alleged price hikes. In the meanwhile, the Frankfurt-based carrier appears to have its eyes set on further European expansion after formally expressing interest in taking over the ailing airlines Norwegian and Alitalia.

Lufthansa, a founding member of the Star Alliance Group, is already the largest aviation company in Europe. The Dax-listed airline with passenger and cargo divisions had nearly 130,000 international employees and recorded gross combined revenue of 35 billion euros (40.8 billion U.S. dollars) in 2017.