A deputy head of the mainland's top planning agency has been sacked for corruption after allegations against him were first posted online, media said yesterday, in Beijing's latest move against pervasive graft. Liu Tienan had been removed as deputy of the National Development and Reform Commission for "serious discipline violations", Xinhua quoted the Communist Party's Organisation Department as saying. President Xi Jinping has promised to tackle corruption, saying it threatens the party's very foundations. Liu's downfall stemmed from allegations first posted online, an increasingly common way of raising corruption accusations by whistleblowers, investigative journalists and citizens. China Daily said in an editorial that Liu was the first ministerial-level official to be investigated stemming from online accusations. "His confirmed investigation is evidence that the authorities are serious about fighting corruption," it said. Besides his position as deputy director, Liu is also a member of a senior group of party officials at the NDRC. Xinhua did not specify from which post he was dismissed, but Liu was no longer listed as deputy director on the NDRC's website. State media reported on Sunday that Liu, 58, was being investigated by the Communist Party organ tasked with probing corruption and other malpractice by party members. Allegations against Liu, who was party chief of the National Energy Administration until March, surfaced when Luo Changping , a senior journalist at influential business magazine Caijing , accused him of improper business dealings late last year. Luo claimed Liu used his position to enrich family members. The energy agency denied those allegations at the time. A source earlier said Liu was brought down by a former mistress who divulged information about Liu.