World leaders, including New Zealand Prime Minister John Key, have been extending condolences to Norway on the bomb attack on Oslo and the shootings at Utoeya Island.
Mr Key described the attacks as an "act of global terrorism".
''I think it shows that no country is immune from that risk,'' at a news conference immediately following a meeting with President Barack Obama at the White House on Friday.
Mr Key said that is why New Zealand is part of the operation in Afghanistan, ''trying to make the world a safer place''.
Mr Obama spoke first and extended his ''personal condolences'' to the people of Norway
British Prime Minister David Cameron has also expressed condolences.
In a phone call to Prime Minister Jens Stoltenberg, he offered assistance in tracking down the perpetrators.
"These attacks are a stark reminder of the threat we all face from terrorism,'' Mr Cameron said.
''I have called Prime Minister Stoltenberg this evening to express my sincere condolences and to let him know that our thoughts are with the Norwegian people at this tragic time.
''I have offered Britain's help, including through our close intelligence cooperation."
Foreign Secretary William Hague said Britain stood ''shoulder-to-shoulder with Norway and all our international allies'' after the ''horrific'' attack.
European Council President Herman Van Rompuy said he was ''deeply shocked'' by ''these acts of cowardice for which there is no justification''.
A Norwegian man has been arrested and is charged with both the bomb attack and the shooting.
The BBC reports that police are investigating whether the attacks were the work of one man or whether he had help.