Five days after Norway's twin terrorist attacks, Norwegian Prime Minister Jens Stoltenberg has warned his country will not be intimidated or threatened.

Speaking to reporters in the capital Oslo on Wednesday, Stoltenberg has said that Norway needed to tolerate views that it did not like “or risk undermining free speech”.

Stoltenberg described the bombing and shooting spree by Anders Behring Breivik as an attack on Norway's fundamental values, democracy and openness. In comments published by the BBC, he added that the response would be “more democracy, and more openness”.

Breivik, who is probably insane according to his lawyer, has admitted to carrying out the attacks — which were aimed at the country's Labor Party, and left at least 76 dead.

(More in-depth coverage from GlobalPost: Is Breivik part of a movement? and Norway's Christian terrorist leads to soul-searching)

Norway's police response to the attacks has been criticized for being too slow.

Stoltenberg said that after a proper period of mourning, Norway would review the police response, adding he welcomed a debate on security:

(Police) organization and capacity will be part of an evaluation. Now is the time for comfort for those who have lost family members [and] friends, and to help those who are still wounded.

Then afterwards, and especially after the investigation is finished, there will be a time for going through all the experiences, learning from what happened and then draw the conclusions regarding, for instance, security measures.

Stoltenberg also said he believed the tragedy would spur an increased interest in political activity in Norway.

• Meanwhile in other news, public broadcaster NRK reported that Oslo's main train station was evacuated early Wednesday after a suspicious suitcase was found.

Norwegian police said the suitcase, which was removed from a bus using a robot, posed no danger.