Chinese artist and government critic Ai Weiwei said he was ordered to take down four live webcams he installed in his home this week to mock authorities' round-the-clock surveillance of him.
Ai, who was held in secret detention for 81 days last year as part of a widespread clampdown on dissent in China, said authorities had telephoned and given him a "clear order" to stop the live feed from his Beijing house.
"They asked me to turn them off, shut them down," the 54-year-old told AFP on Thursday, adding that he was given no reason for the order.
Ai was released from detention last June, but given a one-year probation during which he must stay in Beijing, and lives under almost constant police surveillance.
Before his detention, Ai had angered authorities with his investigation into the collapse of schools in the 2008 Sichuan earthquake and into a 2010 fire at a Shanghai high-rise that killed dozens.
His art work has sold worldwide and he was named the world's most powerful art figure by influential British magazine Art Review last year.
The website hosting Ai's webcam project, http://weiweicam.com, went blank from late Wednesday, as the artist tweeted, "the cameras have been shut down. Byebye to all the voyeurs."
"I explained to them: you have 15 cameras on me, and the camera I set up in my bedroom is exactly the same camera that I had above my head during my 81 detention days," he said on Thursday.
"So I am doing you a favour to (let you) really know what I am doing and have a close watch."