Police want to question a Chinese Embassy official about a Chinese businessman who is suspected of helping Chinese nationals obtain Japanese work visas illegally, sources said Friday.

The Metropolitan Police Department's Public Security Bureau will make the request to meet the diplomat, a counselor in the embassy's consular section, through the Foreign Ministry, the sources said. The Chinese official can decline the request by citing diplomatic immunity.

Police are investigating whether a relationship exists between the official and Tokyo-based consulting firm Chugoku Jigyo Komon, which is run by Zhang Jian, 51. They are also examining the company's cash flow, the sources said.

Police say the diplomat attended a meeting on the unification of China and Taiwan in August last year that was funded by a company affiliated with Zhang's firm.

Zhang used to work in the Chinese Embassy's economic and commercial office and serves as deputy chairman of a Japanese group that wants China and Taiwan to become one country, the sources said.

Tokyo police arrested Zhang in March on suspicion of helping a 61-year-old chiropractor extend his visa by creating documents that falsely stated he worked for Zhang's company as a translator.

Zhang also is suspected of having helped about 70 Chinese nationals obtain visas since 1999 for money. He received about 20 million yen from 20 of the people for services rendered, police said.

Sources said Zhang cannot account for about 100 million yen of the company's money, and police are investigating whether he used the money to fund the activities of the pro-unification group, they said.

Zhang's consultancy was established in April 1996. Its Web site claims the firm has "strong ties" with the Chinese Embassy in Tokyo and the Chinese government.