A murder investigation has been launched into the death of 42-year-old Adrian Greenwood, who was found dead in the hallway of his home in East Oxford on Thursday.Police were called to his three-storey property on Iffley Road at 3pm, after a cleaner found a man inside the hallway.A post-mortem yesterday confirmed the cause of death as multiple stab wounds to the chest and neck.Thames Valley Police believe these wounds were inflicted with a bladed object, but they are yet to recover a murder weapon.They also believe that an altercation took place in the hallway of the house and that Mr. Greenwood died after a “vicious and sustained attack,” in which the offender may also have obtained injuries.A 26-year-old man has been arrested on suspicion of murder and is currently in custody.An onlooker, who saw the arrest yesterday, told Cherwell, “I was walking up the high street at around 18:15 when I saw a small grey car barreling through the high speed with the car horn blaring, closely followed by a police car. Both cars were coming from Cowley. I walked past Quod a few minutes later and saw the two cars parked in the middle of the road. Two policemen, one plain-clothed, were speaking to a man who had a couple of bloody cuts across his cheek.”Detective superintendent Chris Ward, head of Thames Valley Police major crime unit, commented, “We are keeping an open mind in terms of the motive and whilst we have already made an arrest in connection with this investigation, I anticipate further arrests will be made as the investigation continues.”Mr. Greenwood read Philosophy, Politics and Economics at Christ Church before embarking on a career as an antiques dealer, according to his website.On the same site he described himself as a “historian, biographer, author and art dealer with a particular interest in nineteenth century British military history”.He retired four years ago to focus on his writing, producing hundreds of articles since about antiques.A blue tent was erected outside the house, whilst Forensic teams searched through bins, hedges and drains along the street.Hugo Kent-Egan, an Oxford student who lives nearby, commented, “I remember seeing the police tape closing off the section of Iffley Road when I was cycling into college yesterday and wondering what was going on, only saw the story just a few hours ago.“Obviously there are very few details about the incident such as motive and so on, but it was really shocking to read the article and recognise the picture of his house on Iffley Road, just a 5 minute walk from where we live. For something like that to happen virtually on our doorsteps seems very surreal and out of place.“Considering that to most people Oxford seems a very safe and fun place to live and that the only crime I’ve really ever come across this year in Cowley are bicycle thefts or burglaries, something like this really jars with people sense of safety and will perhaps make me more wary this term.”Iffley Road reopened last night after officers were seen removing grey Vauxhall Vectra from the property.However the three-storey house and three nearby properties remained cordoned off this morning.A spokesman said Mr. Greenwood’s next of kin had been informed, although he is yet to be formally identified.UPDATE (April 10 2016): Man arrested by police on the High Street released without charge by police.