"At this early stage, officers are not seeking any further suspects in connection with the incident".
In the first segment, shot from above the area behind the stage, officers can be seen approaching the generator when debris begins to rain down upon them -- a bottle, a brick, a metal chair.
A force spokeswoman said: "At this stage officers believe he sustained the injury as a result of an altercation.
"South Wales police had the systems and intelligence in place to flag up the danger that this offender presented, but, at various stages, officers failed to access that information and to assess the risk properly.
"Clearly in those initial early stages, officers would have been unaware of what had occurred and where the suspect(s) might be and their priority would have been to prevent further injury or loss of life to those in the area".
"As yet, no arrests have been made but our enquiries are still at the very early stages". Officers have asked anyone with information to contact 101 and quote crime reference number 54190020126.
He made little secret of his opposition to the Suez campaign and, at one stage, his officers feared he might desert.
He said he expected the number of police officers needed to fill the gap would reduce in the coming days and there had been no request "at this stage" for officers to provide security at venues.
The men's accusations, if true, would appear to flatly contradict the assurances given by the heads of the three main intelligence agencies when they stepped out of the shadows for the first time last week, telling the intelligence and security committee they have learned a great deal since 9/11, and that "at this stage" their officers could not possibly become complicit in torture.
"The man's next of kin have been informed and the IPCC will provide them with updates on the investigation throughout". At this stage all officers were being treated as witnesses, he said.
