Hong Kong police have violently tackled suspected protesters after thousands of people marched in the city in defiance of a ban.
Images show police hitting people with batons and using pepper spray on a train in Hong Kong's metro.
Police say they were called to the scene amid violence against citizens by "radical protesters".
However it is unclear if all those injured and arrested in the metro system were involved in demonstrations.
People took to the streets on Saturday to mark the fifth anniversary of China's government banning fully democratic elections in Hong Kong.