A man was arrested Friday in north China's Hebei Province for injecting poison into frozen dumplings which were later exported to Japan and sickened 10 people two years ago, local authorities said Saturday.

Lu Yueting, 36, had confessed to injecting a poisonous substance into frozen dumplings when he worked as a temporary employee in Tianyang Food Plant based in north China's Hebei Province, the procuratorate of provincial capital Shijiazhuang City said in a statement.

The crime was an act of revenge as Lu was dissatisfied with his payment and did not get on well with several colleagues, the statement said.

Police had found syringes Lu used to squirt the poison into the dumplings and had several witness accounts, the statement said.

Japanese media reported in January 2008 that 10 people fell ill after eating frozen meat dumplings produced by Tianyang.

Shortly after the incident, the plant was investigated by both Chinese and Japanese authorities, but no problems were found in production.

Before the incident, the plant had been exporting to Japan for 10 years.