A pro-democracy protester was sentenced Friday to nine years in prison in the closely watched first case under Hong Kong's national security law as Beijing tightens control over the territory.

Tong Ying-kit was convicted Tuesday of inciting secession and terrorism for driving his motorcycle into a group of police officers during a July 1, 2020, rally. He carried a flag bearing the banned slogan, "Liberate Hong Kong, revolution of our times."

The ruling Communist Party imposed the security law on the former British colony last year following anti-government protests that erupted in mid-2019.