Of all crimes, cases of riots saw the most significant increase - 58% - last year, latest Delhi Police statistics show.
Cases of riots include the violent protests after the gang rape of the 23-year-old woman para-medic student, agitations by supporters of Arvind Kejriwal and Baba Ramdev, the violence over the Akbarabadi mosque row and clashes in Khoda village in Mayur Vihar phase III.
Against 50 riot cases in 2011, when the capital witnessed several protests by anti-corruption crusader Anna Hazare, the number jumped to 79 in 2012, an increase of 58 per cent.
"Last year, there were more violent protests compared to the previous year. In most of the cases, we were forced to register cases of riots as protesters vandalized public property," said a senior police officer.
Police said that the number of protests started increasing in 2011, which saw two huge movements -- Anna Hazare's anti-corruption movement and Ramdev's campaign against black money.
For most of 2012, the Delhi Police had to deal with similar kind of protests but the last two weeks of the year kept them on their toes. The police had to fire 375 tear gas shells to control the crowd during the anti-rape protests.
"While protests at Akbarabadi mosque and Khoda village were sensitive, protests by Kejriwal was against VIPs and the police had to take strict action to deter them. Though it was a tough task to control the crowds, we tried our best to avoid clashes," the officer added.
In 2012, the Delhi Police handled 8,405 arrangements that included several rallies and demonstrations. "Whenever there is any protest, we have to deploy huge number of personnel to maintain law and order. Heinous crimes do not make one feel tired, but protest duty does. Sometimes, you end up standing for the whole day," the officer said.