Indian police arrested 1,300 people on Tuesday to put an end to a hunger strike by anti-corruption activist Anna Hazare.
The veteran campaigner was himself arrested earlier in the morning at his New Delhi home, just hours before his fast was due to begin.
The Globe and Mail's New Delhi correspondent said that as news of Hazare's arrest spread, protests broke out in Mumbai, Bangalore, Hyderabad, Lucknow and other Indian cities.
Many protesters were rounded up and held at a New Delhi cricket stadium.
Hazare, 74, is protesting an anti-corruption law which is before the Indian parliament. This comes as the Indian government grapples with a series of high-profile corruption scandals.
(Read more on GlobalPost's Bricyard blog: Indian social activist's fast against corruption draws thousands of followers)
India, Asia's third largest economy, has denied the arrests interfere with the right of democratic protest.
The BBC reported that Home Minister P Chidambaram said the detentions came about because protesters had violated conditions for the demonstration.
These include that it did not last longer than three days, and that no more than 5,000 people took part.
Reports say Hazare will be jailed for one week in Delhi's Tihar prison.