HANOI • Vietnam has issued an arrest warrant for a senior official accused of mismanaging a unit of government-run oil giant PetroVietnam, the latest executive targeted in Hanoi's attempt to clean up the corrupt state sector.

Trinh Xuan Thanh, one of the highest-ranking officials to be sought by police in the communist nation in recent years, has not been seen in public since he left the country last month, according to state-run media.

His warrant came just one day after four of his former colleagues at the PetroVietnam Construction (PVC) subsidiary were arrested for allegedly costing the firm nearly US$150 million (S$205.2 million) during his time as chairman.

Vietnam's Public Security Ministry said on its website last Friday that it was seeking Thanh for "intentionally violating state regulations on economic management, causing serious consequences".

Thanh was removed as PVC chairman in 2013 but has since shuffled through a number of senior government postings, including most recently as deputy head of Hau Giang province. He left the country last month for medical care and was stripped of his Communist Party membership last week to pave the way for a probe.

He had been a marked man ever since he was spotted driving a pricey Lexus with a state licence plate, sparking public outrage over inappropriate use of public funds.

Vietnam has been struggling to clean up its vast and inefficient state-run sector for years, and the new communist administration in power since January has vowed to tackle corruption.

Transparency International ranks Vietnam 112 out of 168 on its corruption index, worse than its South-east Asian neighbours Thailand, the Philippines and Myanmar.

AGENCE FRANCE-PRESSE