An activist who has organized numerous petition drives in coastal Ha Tinh province has been arrested under Vietnam’s Article 331, the statute commonly used by authorities to silence those speaking out for human rights.

Hoang Van Luan, 35, was arrested on Wednesday and charged with “abusing democratic freedoms,” according to a statement issued by Ky Anh district police to state media.

At least 15 people across Vietnam have been arrested this year and charged under Article 331, according to a Radio Free Asia tally. The statute has been widely criticized by international communities as being vague.

The arrests under Article 331 are a part of Vietnam’s efforts in recent years to stifle political dissent. Activists are also commonly charged with distributing propaganda against the state under Article 117 of the 2015 Penal Code.

Since 2018, Luan has led petition drives for 18 groups on issues presented to officials at the village, district and provincial levels, as well as at central government offices in Hanoi, Ky Anh police said.

The petitions have included the names of 981 people, police said.

In 2019, police in Hanoi’s Ha Dong district imposed an administration penalty with a warning against Luan, saying his group of petitioners were disrupting social order.

This week, the official People’s Police Newspaper ran a photo of Luan and other petitioners who urged authorities to complete a promised water supply project to improve the lives of residents in the Vung Ang Economic Zone in Ky Anh district.

The Vung Ang zone was the site of a devastating toxic waste spill in 2016. The spill by Taiwan-owned Formosa Plastics Group’s steel plant killed an estimated 115 tons of fish and left fishermen jobless in four coastal provinces, including Ha Tinh.

Luan has also organized petitions in the province that have nothing to do with his family interests, such as the North-South Highway, Ky Anh police said on Wednesday. The petitions have led to delays in land clearance for the project, police said.