Norwegian police say the man who claimed responsibility for the deaths of 77 people in last month's twin attacks in Norway says he traveled abroad in preparation for the attacks, but that he acted alone.

Oslo police prosecutor Christian Hatlo told reporters Thursday that suspected killer Anders Behring Breivik told investigators that he had traveled to many foreign countries to obtain equipment. He said during a long interrogation Wednesday, Breivik also named some companies, claiming he dealt with them.

Breivik's lawyer Geir Lippestad quoted his client as saying he had made about 20 trips abroad to obtain equipment for the attacks.

Hatlo said a team of about 100 investigators is checking if the 32-year-old Breivik had financial and other help, and if he used tax havens. He said police has found no evidence so far that the killer had any accomplices in the July 22 attacks in Oslo and on nearby Utoeya island.

Hatlo said Breivik was calm and collected during the questioning, but that he admitted to struggling with isolation in his cell.

In his 1,500-page anti-Muslim manifesto, Breivik claimed he had collaborated with other extremists.

Police said Thursday they have questioned a blogger called “Fjordman,” whose anti-Muslim writings have been quoted in Breivik's manifesto, but did not reveal what he had said. A Norwegian online news outlet said that the so-called Fjordman had earlier published a statement on the Gates of Vienna website, saying that he has never met Breivik and dislikes being mentioned in his writings.

Breivik is accused of killing eight people in a bombing near government offices in the Norwegian capital, Oslo, then shooting to death 69 people, most of them teenagers, at a Labor Party youth camp on Utoeya, a tiny island. He has said the killings were necessary to his crusade against a Muslim invasion of Europe.

If convicted of terrorism charges, Breivik could face up to 21 years in prison. But alternative arrangements could keep him behind the bars longer.