Officials said Anders Breivik, 33, had a facelift to give him a classic Aryan face, according to The Sunday Telegraph. They reportedly said his look is not common in Norway so he must have had plastic surgery.
Investigators also said it is unlikely Breivik will be able to use an insanity defense because he appeared to be in control of his actions.
By his own account, the 32-year-old Norwegian spent years plotting the attack. On July 22, he set off a car bomb that killed eight people in downtown Oslo's government district, then drove north to a youth camp on Utoya, a small lake island set amid a quiet countryside of pines and spruces.
There, he spent 90 minutes executing 69 people, mostly teenage members of the youth wing of Norway's governing Labor Party.
Breivik, who is being held pending trial, has admitted to the facts of the case, but denies criminal guilt because he believes the massacre was necessary to save Norway and Europe.
The Associated Press contributed to this report.