Ai Weiwei
Media playback is unsupported on your device
Video

China artist Ai Weiwei stopped from boarding flight

Reports from China say the prominent artist and activist Ai Weiwei has been stopped by the authorities from leaving Beijing.

An assistant told the BBC that officials at the airport detained the artist as he was about to board a flight to Hong Kong. There has been no contact with him since.

In the past few weeks, more than 20 Chinese activists have been detained.

Richard Slee reports.