Police in the northern Vinh Phuc Province announced to officially launch the criminal probe on Tuesday, a week after the inspectors were caught in the act.

Initial reports say Nguyen Thi Kim Anh, deputy head of the Anti-Corruption Unit of the ministry's Inspection Division, and her subordinates Dang Hai Anh and Nguyen Thuy Linh, solicited bribes when inspecting several construction projects in Vinh Tuong District in the province, 70 km (43 miles) northwest of Hanoi.

Then they accepted money to let go of several violations regarding cost listings and paper registration.

Vinh Phuc police caught Hai Anh, 38, receiving VND90 million ($3,860) from the representative of a construction firm on June 12.

That same day, Kim Anh, 44, was caught taking VND68 million from Tran Hanh, accountant at the People’s Committee of Tan Tien Commune which is the investor of a local project, and VND91.5 million from another public office's accountant regarding another project.

Hanh said that because the contractor of the commune's project had failed to submit required papers, including a work certificate, Kim Anh told them it was a violation of construction rules and that the commune "should give gifts and money so the inspectors would know what to do."

Investigators later found with them more than VND335 million in cash and many files of construction firms and investors of construction projects in Vinh Tuong District.

The Central Steering Committee for Anti-Corruption on Monday requested related party and the construction ministry to dig into the case of the three inspectors and make report to the committee by the end of the month.

Vietnam's current regulations said one could face 2-15 years in jail for taking bribes. The difference in jail terms will be decided by the value of bribes and the methods of taking it.