Investigators from Japan’s Fair Trade Commission raided the Tokyo headquarters of Apple Japan on Tuesday morning, the company has confirmed.

"We are under investigation and they are in the office now," said Nachi Tamura, a spokeswoman for Apple Japan.

She said the company had yet to confirm the details of the investigation although Japanese public television NHK and the Kyodo News Service both reported the investigation was related to price-fixing on the company's popular iMac personal computer and iBook notebook computer.

Both reports said the PC maker tried to force retailers to sell the machines at prices not below those set by Apple - a violation of Japan’s anti-monopoly law.