According to the Met police there were 20 arrests during the Nov 9 demonstraion in central London (as of 4:45pm yesterday afternoon) They were:
3 x Section 2 and 3 of the Public Order Act (violent disorder and affray respectively)
1 x Offensive Weapon
3 x Going Equipped
1 x Section 60aa
12 x Breach of the Peace
Breach of the peace is not a criminal offence and any arrest would not result in a criminal charge.