File picture of Anders Behring Breivik
A Norwegian commission has criticized authorities for failing to take actions that could have prevented or interrupted the bomb and gun attacks by a far-right fanatic that killed 77 people last year.
The long-awaited report into the July 22 attacks also said the domestic intelligence service could have done more to track down the gunman, but stopped short of saying it could have stopped him.
Anders Behring Breivik has admitted to the bombing of the government's headquarters in Oslo and the subsequent shooting spree at a youth camp, and is awaiting sentencing.
Monday's report said the bombing "could have been prevented" if already adopted security measures had been implemented more effectively.
It also said a more rapid police response could have stopped Breivik's shooting spree on Utoya island earlier.