A former official of Japan Securities Agents Ltd. was arrested Oct. 15 in Tokyo on suspicion of embezzling 550 million yen worth of convertible bonds.Mikizo Uno, 63, is suspected of taking 550 of the bonds belonging to customers and using them as collateral for a loan. Uno, a former section chief at Japan Securities Agents, which provides securities safekeeping services, may have removed as much as 1 billion yen worth of clients' bonds and borrowed about 730 million yen from several consumer finance companies, police said.Uno incurred failures in stock trading around 1990 and used the borrowed money to cover the losses, informed sources said. He was in charge of the company's securities safekeeping services as a temporary employee even after he retired in 1989.