LONDON • The former British intelligence agent who prepared the dossier on Mr Donald Trump's supposed activities in Russia has gone underground.

The strange story of the dossier, which US intelligence agencies, the Federal Bureau of Investigation, Senator John McCain and many journalists have had for weeks, if not months, and which Mr Trump presumably must have known about, appears to have had personal consequences for former spy Christopher Steele.

According to neighbours and news reports, he hurriedly left his home in Surrey, south-west of London, on Wednesday to avoid attention or possible retribution once his identity as the author of the dossier was revealed.

According to The Telegraph, a friend of Mr Steele's said that after his name and nationality were revealed, he had become "terrified for his and his family's safety". His wife and children were also not at home.

The Wall Street Journal reported that Mr Steele had declined its interview requests because the subject was "too hot". The 52-year-old was a longstanding officer with MI6, serving in Paris and Moscow in the 1990s before retiring. In 2009, he started a private research firm, Orbis Business Intelligence, with Mr Christopher Burrows, now 58.

The dossier alleges longstanding communications between Russian officials and Mr Trump's Republican campaign, and that Russian intelligence holds salacious videos involving Mr Trump and prostitutes in Russia. US intelligence agencies have said they cannot substantiate the contents. But the file was used to prepare a two-page appendix to the intelligence presentation US officials gave to Mr Trump last Friday.

Mr Trump, who has denied the allegations in the dossier in the sharpest terms, yesterday accused his political opponents, "both Democrats and Republicans", of putting together the dossier, and said the document was probably released by intelligence agencies.

"Totally made-up facts by sleazebag political operatives, both Democrats and Republicans - fake news! Russia says nothing exists," he said in a series of posts on Twitter. "Probably released by 'Intelligence' even knowing there is no proof, and never will be," he added.

NYTIMES, REUTERS, AGENCE FRANCE-PRESSE