(CNN) -- Norway's police are facing tough questions over their response to last Friday's terror attacks, in which 76 people died.
First, Oslo was rocked by a huge blast outside government buildings, which left eight people dead. Less than two hours later, a gunman reached Utoya island, some 20 miles away, and proceeded to fire on the mostly teenage participants of a political summer camp for well over an hour.
Reporters, particularly from the foreign press, have asked why it took an hour from the police first being alerted for armed officers to arrest the suspect, 32-year-old Anders Behring Breivik.
Among their questions have been why a helicopter was not used to take elite officers to the scene, rather than them travelling by road, and whether problems with a police boat -- which meant civilian vessels had to be commandeered -- delayed the response.
Some have also asked whether the response to the bombing in the Norwegian capital took priority over the Utoya alert, with emergency phone operators and resources already tied up as frantic calls started to come in from young people under fire on the island.
Sissel Hammer, chief of police for the Nordre Buskerud district, which covers Utoya, told reporters Wednesday that her officers and members of an elite police unit had done their best to get to the island quickly.
"I don't think we had any chance to be there faster than we made it," she said.
Responding to the situation in Utoya was "the highest priority" for local police, and was not affected by events in Oslo, she said.
Her staff had done a "very demanding job" both during and after the event, she added.
At the same press conference, Haavard Gaasbakk, who was a commander on the scene, described how he grabbed his equipment and raced to the embarkation point for Utoya when the alarm was raised.
A problem with the engine of the police boat meant the 10 or so emergency personnel who had met there had to take two privately owned motor boats instead, he said.
However, these made the 700-meter crossing of the deep Tyrifjorden lake faster than the police boat would have done, he said.
As they approached, the police heard "a lot of shooting" from the southern part of the wooded island, with gunshots "coming fast and thick," Gaasbakk said.
Officers ran toward the shooting and were about 350 meters away, in very difficult terrain, when they started to shout to the suspect, he said. Suddenly they saw him in front of them with his hands above his head and his weapons -- a rifle and an automatic pistol -- on the ground.
The gunman was arrested by one officer as the others sought to find out of whether he was working alone and started to give first aid to a "conveyor belt" of the injured, Gaasbakk said. He spoke of his pride in the way police and local citizens rallied to help the injured.
Hammer said an evaluation of the police response would be carried out later this year.
A day earlier, police spokesman Johan Fredriksen rejected criticism of the police response to the massacre in Utoya.
"I don't think this could have gone faster," he said. "I don't see how that would be possible with the distance and with these conditions. We always try to be better but I don't see how we could have done this faster."
He said the police had only one helicopter, which is kept at Gardemoen airfield north of Oslo, and that it would not have been suitable to transport a team of counter-terror officers from the capital to the scene.
"It took time to get the staff in. It was filled with irrelevant equipment for the purpose and has never been used for such operations," he said of the helicopter.
"I am of the opinion it would not have been any quicker to use it."
The former police inspector for Oslo, Finn Abrahamsen, told Norwegian reporters he felt it was a pity the helicopter was on the ground on the day of the attack.
Anstein Gjengedal, of Oslo police district -- which pays for the national police helicopter service from its budget -- acknowledged it was flying less hours than it used to because of budget constraints.
Prime Minister Jens Stoltenberg announced an independent commission of inquiry Wednesday, which he said would take an exhaustive look at what had happened and report back within a year on what lessons could be learned.
But he rejected the suggestion that his country was naive and unready for potential attacks, saying Norway's security forces were aware of the danger of violent attacks and were prepared for them.
CNN's Laura Smith-Spark contributed to this report.