The Dutch competition Authority NMa raided the offices of Vodafone, T-Mobile and KPN on Tuesday morning as part of an investigation into price fixing, the authority said.

Vodafone, T-Mobile and KPN confirmed that the raids took place and said they will fully cooperate. The operators are suspected of violating the Dutch Competition Act, which prohibits agreements on pricing and market sharing, according to a spokesman at the NMa.

In a statement, KPN said five employees had been interviewed as part of the investigation. KPN said it educates employees on local competition laws and has internal controls.

T-Mobile is not worried about the outcome of the investigation, a spokesman told Dutch IDG publication Webwereld.

The NMa isn't commenting on how long its investigation will take, he said. The raids followed information given to the NMa from two whistleblowers, Webwereld wrote.

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