London: A British police officer was in Norway on Monday to liaise with police over weekend attacks which killed at least 93 people after it emerged the mass murderer claimed ties with a far-right British group.
At least seven people were killed in a car bomb blast outside government buildings in Oslo on Friday and, hours later, a further 85 were shot dead on the nearby island of Utoeya. One of those injured in the killing spree died in hospital on Sunday.
Thousands attended a memorial service for the victims on Sunday as Anders Behring Breivik, the self-confessed author of the attacks, said he acted alone.
"We do have a Metropolitan Police Service officer in Norway who is liaising with the Norwegian police," a Metropolitan Police spokesman said.
Before the attack, Behring Breivik wrote a 1,500 page manifesto, datelined London, in which he claimed his mentor was an Englishman called Richard, The Daily Telegraph reported on Monday.
Behring Breivik said he was recruited by far-right extremists at a meeting in London in 2002 which was attended by eight people in all, according to the broadsheet.
He boasted that he was one of up to 80 "solo martyr cells" recruited across Western Europe to topple governments tolerant of Islam, it said, adding that Scotland Yard was now trying to establish if he had visited London in recent years.
In the document signed "Andrew Berwick" -- an anglicised version of his name -- he named former prime ministers Tony Blair and Gordon Brown and Britain`s Prince Charles as "Category A" targets for promoting multiculturalism.
The mass killer also spoke of being in touch with the far-right English Defence League.
Foreign Secretary William Hague earlier warned that British security forces would struggle to counter a similar attack, although he said al Qaeda remained the "single biggest threat".
"It`s much harder in the case of a lone individual or a couple of people," he told BBC`s Andrew Marr show. "That is much harder than combating a terrorist network."
About 250,000 Britons visit Norway every year, according to the Foreign Office, and Hague said that the British embassy was ready to help any British nationals caught up in the attack.