The chief operating officer of Cerberus and two other people are being sued by a Japanese company for alleged violation of fiduciary duties, adding to the woes of the embattled US private equity group.

Kokusai Kogyo Holdings is seeking to recover Y52.6bn ($560m) in damages in a lawsuit filed against Mark Neporent, Cerberus’s chief operating officer, and two former directors of Kokusai Kogyo, a bus, hotels and property company, who were appointed by Cerberus.