NEW : Catherine and Catherine visited UK to meet people affected by the riots . Chief Constable Chris Sims said the incident was being treated as attempted murder and arson . Police say three shots were fired at officers and a force helicopter . Police hope members of the public will help them identify those involved . The violence came amid widespread disturbances in English cities earlier this month .
NEW : Catherine and Catherine visited UK to meet people affected by the riots . Police say three shots were fired at officers and a force helicopter . Police hope members of the public will help them identify those involved . The violence came amid widespread disturbances in English cities earlier this month .