BEIJING  -- The dumpling poisoning incident in Japan has been proved to be an individual contrived case, not caused by pesticide residue, said China's quality watchdog on Thursday.

The General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) said at a press conference that it made the conclusion after finding no harmful chemicals in relative products and samples and no abnormal operations by the Chinese producer.

Japanese media reported on January 10 that people fell ill in December and January after consuming frozen meat dumplings produced by Tianyang Food Plant based in north china's Hebei Province.