Police searched a semipublic joint venture in Fukuoka on Thursday on suspicion that it paid exorbitant prices for waterfront landscaping to benefit companies linked to a former local assembly member.

Investigators searched the headquarters of Port of Hakata Development Co., which promotes reclamation projects along the city of Fukuoka's waterfront, and several other locations, including the home of Shinichi Shiki, 65, former president of the firm.

Police said some 50 places will be searched in the case, in which former Port of Hakata Development executives are suspected of committing serious breach of trust.

According to police, the firm purchased 600 zelkova trees and 10,000 tons of garden rocks for a combined 1 billion yen from 1995 to 2001 as part of a project to create an artificial island in Hakata harbor in Fukuoka.