Shanghai, Sep 3 (IANS): Shanghai police have detained a prominent rights activist who called on a local official to resign over the citywide Covid-19 lockdown in April, the media reported.

Ji Xiaolong has been incommunicado, believed detained by the Shanghai state security police, for 24 hours, the RFA reported.

Ji, 46, lives in an expatriate district of Pudong district, and has around 33,000 followers on Twitter, which is banned in China.

His detention came after he began writing petitions to Shanghai ruling Chinese Communist Party (CCP) secretary Li Qiang, calling on him to resign for "blindly following orders from the central government (in Beijing)" when implementing weeks of grueling lockdown in the city earlier this year.

In the petition, Ji wrote that he was fine with being jailed for opposing government policies in an era of widespread internet censorship and surveillance of ordinary people, RFA reported.

He was already under residential surveillance at his home, and police had prevented him from going back to his hometown in Jiangsu's Shazhou county to visit his elderly parents, he wrote.

An activist surnamed Liu from the central province of Hubei said the fact that critics of the government get arrested in China was unsurprising.

"This has become in the norm, in this abnormal country," said Liu, who served a five-year jail term for "incitement to subvert state power" for supporting vulnerable groups.