Police arrested a professional “sokaiya” and two businessmen Monday for allegedly attempting to extort 50 million yen from a Fujitsu Ltd. subsidiary.

Those arrested were Kaoru Ogawa, 62, a well-known sokaiya, Mamoru Ninomiya, 52, the president of a Tokyo construction firm, and Mizuo Saito, 59, a business consultant.

Sokaiya, a common fixture in the Japanese business world, are corporate racketeers who are nominal shareholders in firms. They threaten to disrupt shareholders’ meetings or make public embarrassing or damaging corporate information unless they are paid off. Such payoffs are illegal.

Police said they attempted to exact the money from Fujitsu Business Systems Ltd., a Tokyo-based software developer and construction firm.

The suspects contacted Fujitsu Business Systems staff between January and February, claiming they needed to talk about a house-construction contract that the subsidiary had won, police said.

The subsidiary had already subcontracted part of the job to another company, but the suspects claimed Ninomiya’s firm had obtained an earlier subcontract from Fujitsu Business Systems for the project.

The three men showed Fujitsu Business Systems employees a bogus subcontract, police said.

They demanded that the Fujitsu subsidiary pay 50 million yen in compensation to Ninomiya’s firm, police added.

“You had better pay the money, because it’s very easy for us to destroy a company like yours,” one of the suspects allegedly told employees of the subsidiary, according to police.

Ogawa continued his sokaiya activities even after his arrest in 1993 for extorting money from Kirin Brewery Co. He was later convicted and jailed for attempted extortion in a separate sokaiya case.