Stephen Keogh: Missing man's cause of death unknown
A missing man's skull was found by railway workers nearly four years after he disappeared, an inquest heard.
Stephen Keogh's remains were "semi-buried" in "shallow water" in a tunnel in Bletchley, Milton Keynes, on 21 January.
The rest of his skeleton was found 30m down the tunnel nine days later, Milton Keynes Coroner's Court heard.
His body was too decomposed for a cause of death to be established, but drug paraphernalia was found nearby.
Senior Coroner Tom Osborne recorded an open conclusion.
Mr Keogh was last seen alive in May 2015.
The inquest heard an examination of dental records, identified the remains as those of the 38-year-old, from Netherfield, Milton Keynes.
A post-mortem examination showed "no fresh damage to bones, nothing to indicate an assault had taken place and no evidence of dismemberment," Mr Osborne said.
In a statement, Det Con Ian O'Byrne said a syringe and a tie were recovered from the area the skeleton was found, which Mr Osborne said could be related to drug-use.
Mr O'Byrne said: "We are unable to rule out third-party involvement, but there is no tangible evidence to suggest this.
"It would not be reasonable or proportional to investigate third-party involvement."
Concluding, Mr Osborne said there was "insufficient evidence" to record Mr Keogh's death was a result of a third party, accident or was drug-related.
"Therefore, this is a rare case where I will determine an open conclusion," Mr Osborne said.