Vietnam fired a deputy minister of public security on Wednesday for allegedly aiding a fugitive spy, as communist officials extend their unprecedented anti-corruption drive to the powerful security sector. The one-party state has jailed former officials -- mostly linked to the state oil sector -- along with dozens of bankers and businessmen as part of a widespread campaign to weed out graft in one of Asia's most corrupt countries. The vast and opaque Ministry of Public Security (MPS), one of the country's most powerful and protected institutions, has largely been unscathed in the campaign which critics say also aims to sideline political foes. But on Wednesday the government said an MPS deputy minister Bui Van Thanh was dismissed and had his rank demoted for "serious violations in his work" after he aided a fugitive spy, Phan Van Anh Vu, to travel abroad. Vu, a former property magnate who also worked for MPS, was arrested in Singapore in January carrying two passports -- one fake, one real -- and sent back to Vietnam to face trial. He was jailed for nine years last month for leaking state secrets, though officials have not detailed his crimes, citing national security. The government said Thanh broke the rules in allowing Vu to travel overseas and was stripped of his title. "The Prime Minister implements the disciplinary action by dismissing... Bui Van Thanh," a statement on the government's website said. His rank was lowered from lieutenant general to colonel, the statement added. Thanh was also accused of illegally signing documents approving the sale of state properties, according to an earlier official statement. The dismissal comes as the government launches a major restructuring of MPS, with hundreds of departments to be scrapped in a bid to turn the sprawling ministry into a "lean and effective machine", state media reported this week. Vietnam's vast police force -- both uniformed and plainclothes -- and parts of the cybersecurity and intelligence units fall under the MPS umbrella, though staffing numbers are not made public. Earlier this year, several high-ranking MPS officers were arrested for running a massive online gambling ring, including the official in charge of policing internet betting. Vietnam's anti-corruption campaign, waged by a conservative leadership in charge since 2016, has stunned a public unused to seeing powerful figures publicly punished. Observers say the drive is aimed at cleaning up graft -- but is also driven by political infighting. Though Vietnam has one of the region's best performing economies, it is plagued by corruption, ranking 107 out of 180 on Transparency International's corruption Index, behind Thailand, Indonesia and China.