One of 12 Hong Kong people held by the mainland coastguard two years ago for crossing the border illegally has been given 20 months in prison here after pleading guilty to making explosives during the 2019 social unrest.

The District Court heard that 31-year-old Wong Wai-yin, a mechanic, made the explosive DNT near Ng Uk Village on Sha Tau Kok Road between December 1, 2019 and January 14, 2020.

Prosecutors agreed to drop a charge of perverting the course of justice.

Wong, along with 11 others, was intercepted at sea by the Guangdong coastguard on August 23, 2020 when the group was reportedly fleeing to Taiwan on a speedboat.

He was sent back to the SAR in March last year after completing his seven-month sentence across the border.