Russian oligarch Boris Berezovsky was found lying on the bathroom floor at his British home with a ligature around his neck and the same material on a shower rail, an inquest into his death heard on Thursday.
The 67-year-old Kremlin critic was found dead on Saturday in his mansion in Ascot, west of London, sparking frenzied speculation about how he died.
A post-mortem examination found his death was consistent with hanging, but toxicology tests are being carried out and it will be several weeks before the results are known.
At the opening of the inquest in Britain, Detective Inspector Mark Bissell said Berezovsky was found with a "ligature around his neck and a piece of similar material on the shower rail above him".
Although the post-mortem found no evidence of a violent struggle, the detective said the involvement of a third party "cannot be completely eliminated as tests remain outstanding".
Berezovsky's body was found by an employee -- believed to be a bodyguard -- on Saturday afternoon.
Bissell told the inquest that the employee had last seen Berezovsky alive at around 9:00 pm the night before.
The inquest was opened and adjourned. Inquests in Britain are held into all unexplained deaths to establish the facts, but do not apportion blame.
In the family's first public response to the death, Berezovsky's daughter Anastasia Berezovskaya said Wednesday he was not a "typical parent" and described him as an "extraordinary" man.
Berezovsky fled to Britain in 2000 and used his British base to launch verbal attacks on the Kremlin and President Vladimir Putin from exile.
Friends have said he had become deeply depressed after losing a multi-million-pound court case against fellow British-based Russian oligarch Roman Abramovich last year.
Forbes magazine published an interview on its website that Berezovsky gave shortly before his death in which he said his "life no longer makes sense" and that all he wanted to do was return to Russia.
But despite the signs that he apparently took his own life, speculation about Berezovsky's death is inevitable. He survived several assassination attempts, including a bomb attack that decapitated his chauffeur.
His friend and fellow Kremlin critic Alexander Litvinenko was killed by radioactive poisoning in London in 2006, in what Litvinenko's widow believes was an assassination.
A friend of Berezovsky, Alexander Goldfarb, told AFP outside the court: "My personal view is that Boris was not the kind of man to commit suicide.
"But then again, he was under a lot of stress over the past several months, and over the past 13 years (while opposing Putin), so eventually this might have taken its toll."
Berezovsky had had a turbulent private life in recent years.
His divorce from second wife Galina Besharova in 2011 was dubbed one of the costliest in Britain. Reports suggested the settlement was worth more than £100 million ($150 million, 120 million euros).
He had also split up recently with his latest partner, Elena Gorbunova.