A Beijing procurator confirmed on Monday five people are under judicial investigation for leaking key economic data prior to its official release.

Zhang Huawei, a director from the Beijing People's Procuratorate, told chinanews.com that the five people, including a staff member responsible for the secretarial work of the National Bureau of Statistics (NBS)'s administrative office, are under investigation.

The news portal said the CPI data was apparently leaked to institutions, and some foreign news agency has correctly "guessed" the CPI data seven times since 2008.

According to data released by NBS on June 14, the CPI rose 5.5 percent year-on-year in May, the same as many institutions had reported several days before.