The trial of a prominent human rights lawyer began in northern China on Wednesday with about two dozen plainclothes officers stationed outside a courthouse and at least one supporter taken away by police.

Reporters, foreign diplomats and supporters were prevented from approaching the municipal court in Tianjin city where lawyer Wang Quanzhang was being tried. Wang's wife, Li Wenzu, was kept from attending the proceedings by security agents who had blocked the exit of her apartment complex since Tuesday.

Li told The Associated Press by phone Wednesday that Liu Weiguo, Wang's government-appointed lawyer, confirmed the trial had started. But he did not tell her whether it was now over or whether a verdict had been reached.

The court said in a statement on its website that it "lawfully decided not to make public" the trial hearings because the case involved state secrets. A decision will be announced at a future date, the court said.

Wang is among more than 200 lawyers and legal activists who were detained in a sweeping 2015 crackdown. A member of the Fengrui law firm, among the most recognized in the field broadly known in China as "rights defending," he was charged with subversion of state power in 2016. He has been held without access to his lawyers or family for more than three years.

Fengrui has pursued numerous sensitive cases and represented outspoken critics of the ruling Communist Party. Wang represented members of the Falun Gong meditation sect that the government has relentlessly suppressed since banning it as an "evil cult" in 1999. Group leaders have been sentenced to lengthy prison terms and ordinary followers locked up as alleged threats.