HONG KONG (AP) — Prominent Hong Kong activist Joshua Wong on Friday was charged with conspiracy to collude with foreign forces to endanger national security under a Beijing-imposed law that critics say has crushed Hong Kong's once-thriving pro-democracy movement.

The prosecution was the second time Wong has been charged under the sweeping national security law. He was already convicted in a separate subversion case linked to an unofficial primary election and is serving a sentence of four years and eight months.

The prosecution accused Wong, 28, of conspiring with fellow activist Nathan Law and others to ask foreign countries, institutions, organizations and individuals outside of China to impose sanctions or blockades, or engage in other hostile actions, against Hong Kong and China.

They also said he disrupted the formulation and implementation of laws and policies by the Chinese and Hong Kong governments, and that the act was likely to have serious consequences. The alleged offense occurred between July 2020 and November 2020.

The prosecution didn't elaborate on the accusations in court. The charge carries a maximum penalty of life imprisonment.

After hearing the charge in court, Wong, who wore a blue shirt and was visibly thinner, said he “understood” the charge.

The case was adjourned to August.

National security police arrested Wong in Stanley, an area in southern Hong Kong, over the national security charge and also on suspicion of “dealing with property known or believed to represent proceeds of indictable offense," police said in a statement.

Wong rose to fame in Hong Kong in 2012 as a high school student leading protests against the introduction of national education in the city’s schools. Two years later, he became world famous as a leader of the Occupy Movement.

In 2016, Wong co-founded a political party named “Demosisto” with fellow young activists Law and Agnes Chow. In the 2019 pro-democracy movement, Wong helped seek overseas support for the protests. His activism led Beijing to label him an advocate of Hong Kong’s independence who “begged for interference” by foreign forces.

Demosisto disbanded when Beijing imposed the security law in 2020. The Chinese and Hong Kong governments said the law brought back stability to the city.