LONDON , England ( CNN ) -- The 2005 London bombings on three subway trains and a bus , which killed 52 people , could not have been prevented , according to an official report into the attacks released Tuesday . The wreck of a bus destroyed by a bomb in central London on July 7 , 2005 . Police and intelligence services did all they could to trace suspects and avert attacks given the resources , intelligence and evidence they had at the time , said the report by the Intelligence and Security Committee , which reports directly to the prime minister . `` It is a very shocking fact , and it 's one we have to live with , '' said Kim Howells , a lawmaker who chairs the committee . Some 700 people were wounded in the bombings on July 7 , 2005 . All four bombers died in the blasts . The finding contradicts portions of the committee 's 2006 report into the bombings , which said the chances of preventing the attacks could have been increased . Having additional resources in place might have alerted law enforcement agencies to the intentions of the July 7 bombers , the 2006 report said . Watch what the new inquiry concludes » . But the report released Tuesday said it would have been impossible to trace every person connected to the plot . `` If you want complete coverage , you 're going to have to have hundreds of thousands -- literally -- of security and intelligence officers , and that 's not the society we live in , '' Howells said at a news conference . `` I 'm afraid that it is an extremely uncomfortable fact . '' Law enforcement agencies could not have simply shifted resources to cover areas that needed attention , the committee said , because other operations were deemed more urgent at the time and officers had to make `` hard choices '' about the suspects and leads it wanted to pursue . `` Hindsight is a wonderful thing , '' said committee member Michael Mates . `` Having gone into all the details , we ca n't find any reason to criticize the judgment they took at that time . '' He added , `` I wish we could say it wo n't happen again , but we ca n't . '' Resources are only part of the problem , the committee said . `` It is not simply a case of 'throwing money at the problem ' -- MI5 operates under legal constraints , too , '' the report said . MI5 is Britain 's domestic intelligence agency . `` MI5 must have good reason to investigate an individual before they are permitted to use intrusive techniques -- the law is designed to protect an individual 's right to privacy . '' Under the law , there was no reason for police to have followed some of the people now deemed to have been involved in the attacks . Surveillance or further investigation simply was n't justified in the months before the attacks , said committee member George Howarth . `` With hindsight , we are now able to consider past events , connect them and understand what might have been happening . But this is only with the benefit of hindsight , '' the report said . Police coverage is now better than it was , Mates said , and he praised the British government for spending more on law enforcement and the security agencies for recruiting more staff . The committee did , however , criticize the communication between police and security services , just as the previous report did . It also criticized the record-keeping of MI5 . It is the panel 's most comprehensive report yet into the 2005 attacks . The committee looked at every detail that police and intelligence agents knew , including recordings , photographs , and records . It aimed to deliver a more complete report than the one issued in 2006 , Howells said . The final result took more than 14 months to produce and ran to more than 100 pages . `` We appreciate that everyone wants to be reassured that there will never be another 7/7 . Such an absolute assurance can not be given , '' the report says . `` What our agencies can do is to build an intelligence network that gives them as much information as possible and then try and stop those that it comes across -- which is what they have been doing . But we must be realistic . Despite the increased efforts of the agencies , and the increased resources at their disposal , the odds are stacked against them . ''
Note : Police and intelligence services did all they could to trace suspects . Impossible to trace every person connected to the plot , it added . # ##4 , 700 people were killed in July 7 , London bombings . All four bombers died in the blasts in central London .