Kajima used cheap gravel at Haneda

Kajima Corp., one of Japan's five largest general contractors, is suspected of using low-priced gravel in the construction of a new runway at Tokyo's Haneda airport and making unfair profits, land ministry officials said Friday.

The Ministry of Land, Infrastructure, Transport and Tourism plans to soon file a complaint with police against Kajima on suspicion of fraud, the officials said. The ministry believes Kajima unfairly gained several million yen in unfair profits — the difference between the contract price and the actual cost.

In February, a ministry investigation found that Kajima had used cheap gravel rather than high-priced landfill material in the runway construction under contract. The ministry issued Kajima a warning in June and the company removed the gravel from the runway construction site in August.

Kajima collected the gravel in 2007 from a building construction site in Yokohama.