Police searched an office of Kajima Corp. and other locations Wednesday on suspicion the major contractor cheated the government out of roughly ¥4.7 million for work on the new runway at Tokyo's Haneda airport.

Kajima allegedly used 1,190 cu. meters of low-cost gravel for embankment work instead of the gravel approved by the government, according to a complaint filed with the police by the transport ministry.

The Metropolitan Police Department searched such locations as Kajima's field office in Koto Ward, Tokyo, and the office of a subcontractor.

Kajima, which removed the cheap gravel in August, said it was used by mistake due to miscommunication with a subcontractor, and it was not deliberate.

The company said it had no intention of committing fraud over the construction fees or making illegal profits.