Image copyright Reuters
Mr Ai posted footage of the demolition on social media
The dissident Chinese artist Ai Weiwei says the authorities in Beijing have demolished his studio there.
In a series of clips on Instagram showing the former factory being torn down, Ai stated that he had been given no notice of the decision.
Another of his studios in Shanghai was destroyed in 2011. He also said at that time he had received no warning.
The 66-year-old has lived in Germany since leaving China in 2015. He is a strong critic of China's government.
On Instagram Ai said "farewell" to the space, which he had used since 2006.
One of Ai's assistants, Gang Ra, told the AFP new agency that the rental contract for the building had ended last year but that it "simply wasn't possible" to move out at the time because of the amount of works still present.
He stated that they had been told that the move would need to take place within a matter of days, but added that they had not been warned when the demolition would begin.