Reddit User Sunberg put together a very in-depth collection of information surrounding the shooting in Oslo that I’ve featured below. WARNING: Some of the links below lead to images and video that are very graphic in nature.
Some bulletpoints of what happened:
This happened at the Norwegian Labour party’s summercamp for teenagers.
ca 600-700 people were at the island (Utøya is an island) most of them teenagers around 16 years old
The island is about 35km / 20miles from Oslo
The island is about 0.12km2 , or easier to visualize: 350 x 350 meters. It was also about 500-600 meter swim to get to the mainland. (via Humpa )
Some people were trying to swim others were hiding
Some people were saying that if you know someone there, don’t call them as they might have been hiding
People were posting to Facebook and Twitter asking for help
(19:10) One person was arrested.
Photos show that many teenagers have been killed
The shooter used many weapons, including shotgun, handgun and automatic weapon.
Uncensored photo from the island
Total death toll is atleast 80, and police are saying it may still rise. Most of them children/teenagers.
Police have also found unexploded explosives on the island, and believes/almost certain that there is a link with the Oslo bombing 2 hours earlier.
Around 30 are seriously injured, among those 20 are critically injured
Breivik had purchased 6 tons of artificial fertilizers on the 4th of May. This is not considered unusual for a vegetable producer.
Update 09:14 Norwegian time:
At least 84 have been confirmed dead at the island, but numbers might still rise. None of the dead have been identified yet, and the police are still searching for bodies on land, but mainly in the water as he also shot at people trying to swim from the island.
The shooter has been charged with the maximum sentence possible in Norway (21 years in prison, however, this can be raised up until life)
The shooter has been charged for both the Oslo explosion and the shootings
Update 09:30:
Police has raised the estimate to a total of 91 confirmed dead at Utøya (84) and Oslo (7)
Update 15:55:
Dagbladet writes that the police has confirmed that 85 people were killed at Utøya. However, they say numbers may still rise.
About the shooter:
He has been arrested and is being questioned by the police. This is what I have been able to gather of info so far. Police are still considering the possibility that he did not act alone.
Name: Anders Behring Breivik
Age: 32
Ethnicity: Norwegian
Considers himself a nationalist
Interviewed childhood friends says he turned extreme right wing towards the end of his 20s.
No earlier crimes and is unknown to the police
Considers himself conservative Christian
Started a company in 2009 called Geofarm and stated it would do farming. Using this company he got access to a lot of artifical fertilizers (means that this has been planned for some time)
Created a Twitter account 1 month ago and has only tweeted one tweet: «One person with a belief is equal to the force of 100 000 who have only interests»
Has been very active on online communities against “internationalism” (Document.no is one such site and has published all of his posts as a response to the events - norsk/english.)
Has strong opinions against immigrants, especially muslims
Is member of a pistol club and is a registered gun owner - has 2 registered guns
Lived most his life in Oslo (west side), but recently moved to Hedemark (further north)
Freemasonry member
Was a member of FrpU, the youth wing of Frp ).
About the theory that may have been more shooters:
Police just arrested a young man at a hotel close by in possession of a knife. He claimed he did not feel safe and it is still unconfirmed if he was involved in the massacre. He claimed he was a member of the Labour youth party (more)
Some news sources say the police are concerned that a second shooter might be free while others say are not looking for anyone in particular and nothing is conclusive (more) (more)
Some news sources say witnesses describe a second shooter dressed in civilian clothing and that police are investigating the witness statements. (more)
Witness stories:
(Note: the translation may not be 100% accurate)
“He came to the island saying he was a police officer. Asked everyone to gather around and then began to shoot. He shot widely around himself. First no one believed that it actually was happening. We thought it was just bullshit, until we saw people with blood and… yeah… Then everyone began to run.”
Did you see anyone who were dead? ”I… many. Very many.” Can you say a number? ”Around 15 when I was there trying to help by the beach. People were either shot or had drowned in the water. It was not a good sight. Everyone ran towards the forrest. There were injured people who we carried. People tried to hide, but then he came to them saying he was the police here to rescue them. When people approached him he shot them.” (more in the video)
“The first thing he did was to shoot the cutest girl he saw.” (article)
“He reloaded, shot more. He shot around me. I was lying still thinking: this is the end”. She played dead over 1 hour lying among bodies (article / blog post by the witness)
“He shot people in the head to make sure they were dead” (article)
“I felt the heat from his gun” … “Some people ran and hid in their tents. He went systematically from tent to tent with an automatic rifle and fired single shots. It was apparent that he wanted every shot to count.” … “Many took off their clothes and tried to swim. I tried to swim with my clothes on, which began to get heavy in the water, so I had to turn around. I hid on the beach with another group. He eventually came back and fired into the group. I played dead and lied down among the bodies. At the closest he was 2-3 meters away from me.” Adrian Pracon, a survivor, was shot in the shoulder ”I did not feel the shot at first. It was very loud and I was deaf in one ear for a while. It felt like pinch. The pain came afterwards” … “It almost seemed like he had done this before. Walking around and shooting people seemed normal to him.” (article)
NSFL:
Video from the island:
https://www.youtube.com/watch?v=Hj2ySvguk9M&skipcontrinter=1 (via pooprocks)
Shooter mid-spree:
https://i.imgur.com/KgUmy.jpg (via tyeg)
Video of the island filmed from a boat. Those white spots are bodies covered with plastic or towels. Police are still looking in the water, and numbers may still rise:
http://www.vgtv.no/#!id=42425 Sources:
http://pastebin.com/BN2jT5CUGot this off tumblr. Looks kinda whack since I just copy pasted it but w/e
Subject: Situation in Norway 
Sat Jul 23, 2011 4:59 pm
