Police raided his home in the central city of Da Nang on December 21 and issued an arrest warrant against him for revealing state secrets. They did not say what the state secrets were.

Investigators are looking into three dozen properties that were had previously belonged to the state and were reportedly sold to Vu at below market price.

Vu was arrested in Singapore after using a false identity to enter the country last week, Singapore’s Ministry of Home Affairs said.

“He had entered Singapore using a Vietnamese passport bearing a false identity” and carried two other passports, the ministry said.

It said Vu was deported for immigration offences, but added that he was wanted under an Interpol Red Notice issued by Vietnam.

Vu’s lawyer in Singapore, Choo Zheng Xi, said the crimes his client is accused of back home could lead to a severe penalty, adding: “He was extremely stressed and frightened for his safety should he be returned to Vietnam.”

Vietnam has stepped up its fight against corruption in recent months.

Germany in August accused Vietnam of kidnapping a former oil executive from a Berlin park. Vietnam rejected the accusation, saying Trinh Xuan Thanh returned home voluntarily to face justice.

The incident strained relations between Vietnam and Germany and Berlin expelled two Vietnamese diplomats in retaliation.

Thanh along with Dinh La Thang, a former member of Vietnam’s all-powerful Politburo and a former chairman of state energy giant PetroVietnam, and 20 other executives are expected to stand trial next week for their roles in the alleged mismanagement of the construction of a power plant.

Thang will be the first former Politburo member to face trial in decades.