Two Christian pastors in Vietnam recently had a taste of Vietnamese-style persecution when they were kidnapped, stripped, robbed and beaten with metal rods by a group of men who they suspect were working for the police.

Interviewed by Radio Free Asia, Protestant clergyman Rev. Nguyen Trung Ton said he and fellow pastor Rev. Nguyen Viet Tu were abducted by unidentified men in late February after they arrived at a local airport.

Ton, a pro-democracy Vietnamese activist in who had previously been imprisoned for his activism, said he and Tu were on their way to meet up with other activists when they were pounced upon by the suspects who loaded them into a van after beating them, Asia News reported.

Ton said their kidnappers covered their heads to prevent them from knowing where they would be taken. He said they stopped at a secluded wooded area where the suspects beat them again using metal rods. They were also stripped of their clothes and robbed.

After the suspects left, local residents found the wounded pastors and helped them.

Vietnam ranks 17th on Open Doors USA's 2017 World Watch List of top Christian persecuting countries. Among Asian countries in the list, Vietnam is ranked as the fifth worst after North Korea (#1), Afghanistan (#3), Pakistan (#4), and India (#15).

Last November, Vietnam's communist government adopted a new law that severely curtails freedom of religion.

In January, security forces reportedly arrested students gathered for a Bible class at a school in the capital Hanoi.

"We were arrested by Hanoi security during our Bible class. All students had to stay in the police station and were divided one-by-one to write about what we were doing. The foreign missionary leading our class was charged $1,000 and expelled from the country," one pastor told Open Doors USA.

The Christian persecution watchdog said Christian persecution is mounting in Vietnam, a country where Christian communities are often subject to arrests and land grabbing by the authorities.

Buddhists who converted to Christianity reportedly face the strongest persecution not only from the authorities, but also from their families, friends and neighbours.