Mystery surrounds the death of a 33-year-old drug addict found with more than 15 times the lethal dose of morphine in his system.

Stuart Davis was found by his girlfriend Sarah Lea Kingston slumped in the hallway cupboard of the flat they shared in Purs Lane, Abingdon on January 18, this year.

A post mortem examination found he had 1,900mg of opiates per litre of blood.

However, an inquest in Oxford was told it was unclear how, or when, the drug had been taken.

Giving the cause of death as a morphine overdose, consultant pathologist Dr Peter Millard, of the John Radcliffe Hospital in Oxford, said: "I have heard no evidence of how he took it."