HANOI: A court in Vietnam's capital on Tuesday sentenced six executives of a state-owned railway corporation to up to 12 years in prison after convicting them of corruption involving a Japan-funded railway project.

Pham Hai Bang, deputy director of the Railways Project Management Unit under Vietnam Railways Corp., was sentenced to 12 years in prison on charges of "abusing power and authority while carrying out official duty." Five other executives were given sentences ranging from 5 1/2 to 11 years at the end of a two-day trial.

In announcing the sentences, Judge Truong Viet Toan said the defendants' crimes were very serious, negatively affecting the country's image and forcing the railway project in Hanoi to be temporarily suspended.

"The acts of abusing power and authority of the defendants ... have affected Vietnam's prestige, affected the cooperation between Vietnam and Japan in using the official development assistance," Toan said.

The defendants were convicted of abusing power to force the consulting joint venture, led by Tokyo-based Japanese Transportation Consultants, or JTC, to pay 11 billion Vietnamese dong ($550,000) from 2009 to 2014. Most of the money was spent on organizing a contract signing ceremony, workshops, document printing and bonuses.

The defendants and their lawyers argued that JTC voluntarily gave the money to facilitate execution of the project using the official development assistance funds from Japan, but prosecutors determined that JTC was forced to give the money against its will.

The case came to light in March last year when executives of a Japanese firm consulting the project admitted to Japanese prosecutors that they paid kickbacks worth 130 million yen (about $1.3 million) to civil servants in Vietnam, Indonesia and Uzbekistan in return for consulting contracts.

In 2010, a senior official in Vietnam's southern commercial hub of Ho Chi Minh city was sentenced to life in prison for bribery after being convicted of receiving $262,000 from a Japanese consulting firm for an infrastructure project in the city using preferential loans from Japan. The case led Japan, Vietnam's largest foreign donor, to briefly suspend the ODA loans to the Communist country.