China human rights
Family members and lawyers of detained lawyers and their colleagues gather after another attempt to seek answers at the Hexi District Detention Centre in Tianjin on 8 January 2016FRED DUFOUR/AFP/Getty Images

The US has condemned China's recent crackdown on human rights activists and lawyers after a court jailed four of them on charges of "subversion of state power". On 2 August, prominent human rights activist Hu Shigen was jailed for more than seven years, while Zhai Yanmin (also an activist) and lawyers Zhou Shifeng and Gou Hongguo were handed three to seven-and-a-half years in jail by a court in the northeastern city of Tianjin.

Washington called on Beijing on Monday (9 August) and sought the release of the four activists. China has been accused of silencing government critics by detaining them unlawfully.

Spokeswoman from the US State Department, Elizabeth Trudeau said in a statement: "We urge Chinese authorities to release the lawyers and rights defenders who are imprisoned or in detention, including those already sentenced."

"More than a dozen other attorneys and activists detained on and around 9 July, 2015, including Li Heping, remain in pre-trail detention without access to their families or to legal counsel of their own choosing," the US state department statement said, Reuters reported.

"We call for an immediate end to the cases brought against them and to restrictions on their freedom of movement and professional activities," it added.

According to BBC, around 300 such lawyers and activists have been arrested since last year as part of the country's nationwide crackdown on those critical of the government. Around 20 of those arrested are reportedly still under detention. Several people, including the four sentenced last week, are believed to be linked to a law firm named Fengrui in Beijing.

Chinese media reports said that Shigen – one of the convicts who has been stripped off his political rights for five years – pleaded guilty for being connected to "foreign anti-China forces" and admitted that he plotted with members of the law firm "to get lawyers involved with sensitive incidents".

Over the past year, Chinese President Xi Jinping's administration has attempted to strengthen the country's security and social stability from being damaged by so called "dissidents". The government has claimed that there are anti-China activists who are conspiring to overthrow the Communist Party.

Further, family members of the detained activists have complained against authorities for not allowing them to meet their relatives in prison.