HANOI (REUTERS) - Vietnam's ruling Communist Party demoted a prominent party official on Wednesday (May 10), stripping him of his role as party head of Ho Chi Minh City to penalise him further for misconduct during his time as head of the country's state oil and gas firm.

On Sunday (May 7), the party dismissed Dinh La Thang, 56, from its politburo after finding him responsible for financial losses at PetroVietnam, various illegal projects, and an excessive stake purchased in Ocean Group's banking unit.

Following up on that unusually strong action against an incumbent high profile official, the party said on its website it has also removed Thang from his role as party chief in the country's economic hub and biggest city, and re-assigned him as vice head of the central party's economic committee, to drop him further down the party's ranks.

"The central committee's decision to discipline me is reasonable," local media Tuoi Tre online quoted Thang as saying at the announcement ceremony on Wednesday morning (May 10).

Nguyen Thien Nhan, head of Vietnam's Fatherland Front and a politburo member, was named as the new party chief for Ho Chi Minh City. No replacement for Thang on the politburo has been named.

Vietnam has cracked down on corruption at PetroVietnam and its subsidiaries, including Drilling Mud Corp. Several senior officials have been detained, and some are facing possible sanctions.

The party had said Thang committed "weaknesses and serious violations in his leadership, command and staff works...sparking annoyance among officials, party members and the people" while he was chairman of PetroVietnam between 2009-2011.

Thang was an unusually outspoken official among normally-reticent Communist Party apparatchiks, known for his forthright comments on sensitive issues. He headed several state firms and the transport ministry before entering the politburo in 2016.