Bullets were still hitting the water when police arrived to stop the massacre on the Norwegian island of Utoeya, the officer who led the operation said Wednesday.
The officer spoke as the prime minister announced an independent review to draw lessons from, as it emerged that police efforts to apprehend the gunman were hampered by engine trouble.
Haavard Gaasbakk, who headed the intervention team, defended his men against criticism from some quarters that they were too slow to get to the scene.
Gaasbakk said he was proud of his men's work Friday, the day self-confessed killer Anders Behring Breivik went on the rampage and shot dead 68 people on the island.
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"They were extremely solid and showed much courage right down the line," Gaasbakk said.
According to the official version of events, it took police just over an hour after receiving the first message about the shootings on the island, 40 kilometres (25 miles) from Oslo, to arrest Behring Breivik.
They launched their operation shortly after the car bomb in central Oslo that killed eight people, tying up emergency services there. And along the way, they had to improvise after a police boat suffered engine problems.
An official timeline released on Sunday showed that local police got the first call about the shootings at 5:26 pm (1526 GMT).
Gaasbakk said he got called in from a day off and arrived at Hoenefoss police station, which covers Utoeya island, at 5:43 pm, less than 20 minutes later.
"I understood it was serious. I had seen what had happened in Oslo and I made the connection" with the shooting, he added.
Once Gaasbakk and his team were armed, an exception rather than the rule for Norwegian police, they made their way down to the lake, a few kilometres away, to make the crossing to Utoeya.
There were joined at the lake by an intervention team sent from Oslo at the request of local police.
In all, 10 men boarded the police launch, said Gaasbakk.
"On the way, the police boat had engine problems," he recounted.
"But at the same time, private boats came towards us to say what was happening. We had them come over to us and requisitioned them."
Now, the police officers were travelling in two boats, both of them faster than the launch they had abandoned.
According to one senior police officer, this meant that they got to the island "perhaps 10 minutes" earlier than they would otherwise have done.
One of the two boats arrived about 30 seconds to a minute before the other, heading to the north of the island, following the desperate signals of terrified survivors on the island, said Gaasbakk.
He was on the second boat.
"We could see the impact of bullets in the water at a point south of the island," he said. "There was constant gunfire."
"We beached and we ran directly towards the southern point. We had to run 300 to 350 metres (990 to 1155 feet). When we approached the gunfire, we shouted: 'Police, we are armed'."
The five officers then arrived in a wooded area. "Suddenly, the shooter was in front of us, his hands in the air," said Gaasbakk.
Behring Breivik had left his weapon a good 15 metres away.
One of the officers arrested him; the others went to see to the wounded.
It was 6:27 pm.
