A woman in the choir reacts as Norway's Prime Minister Jens Stoltenberg makes an address during a service at Oslo Cathedral Sunday July 24, 2011, in the aftermath of terror attacks Friday on Norway's government headquarters in Oslo and a youth retreat on Utoya island. Police said Sunday they are conducting an operation in a residential neighborhood of Oslo, and police spokesman Anders Fridenberg would give no other details about the action. Survivors of the massacre have said there were two assailants, and police have said they were looking into those accounts and had not ruled out a second suspect. (AP Photo/Matt Dunham)