How did Violent Disorder Start in Leeds?

How did violent disorder start in Leeds?

Police in Leeds say they’ve made a number of arrests after last night’s violent disorder in the Harehills area of the city – warning that more arrests would come in the next few days.
The unrest was sparked after social workers took several children into care.
Police officers were attacked by a crowd throwing bricks and missiles – and a bus was set on fire.
Credit to : Channel 4 News