Amid suspicions that bids were rigged for contracts involving the Defense Facilities Administration Agency, the president of a Tokyo-based construction materials company allegedly acted as an intermediary for electrical machinery companies seeking orders from the agency.

Investigative sources said Sunday the 53-year-old president of N-Tech was working as the secretary of a veteran lawmaker when the bidding on the electrical installation projects was taking place in the 1980s.

The lawmaker had served as parliamentary vice minister at the Defense Agency and posts and telecommunications minister. He retired in 1990.

N-Tech is suspected of playing a major role in the alleged bid-rigging.

Investigators at the Tokyo District Public Prosecutor's Office have already questioned the president on a voluntary basis, the sources said.

He has confirmed receiving consulting fees from the companies but denied any illegal conduct, they said.

The former lawmaker, now 81, a medical doctor hailing from Hokkaido, was first elected to the House of Representatives in 1967.