A thrill-seeking hospital nurse who gave patients deadly injections so he could enjoy the excitement of reviving them was yesterday found guilty of murder.

Benjamin Geen (25) gave a total of 17 victims the injections between December 2003 and February 2004.

Fifteen patients survived, but two died.

David Onley, aged 75, of Deddington, Oxfordshire, died on January 21, 2004, and Anthony Bateman, 65, of Banbury, Oxfordshire, died on January 6, 2004, shortly after they were admitted to the Accident and Emergency department of the Horton General Hospital in Banbury, Oxfordshire, where Geen worked as a staff nurse.

As well as the two murders, Geen was found guilty of causing grievous bodily harm (GBH) to 15 patients. He was acquitted of causing GBH to 93-year-old Heinrich Zinram.

The officer leading the investigation, Detective Superintendent Andy Taylor, said Geen would have killed again had he not been stopped.

He and his officers worked for months with the help of experts to piece together the medical evidence, and sought advice from police who investigated the cases of serial killer Dr Harold Shipman and child murderer nurse Beverley Allitt.

Mr Taylor said Geen was "almost narcissistic in his desperate desire to be noticed", a man who was becoming more brazen in his attacks.

Mr Justice Crane echoed this view, and asked for psychological reports to explain Geen's bizarre motive.

He said: "These are such unusual offences and the motive is such a strange one and not in any sense entirely normal, I think I should not sentence until I have got a full picture."

The jury of six men and six women heard how Geen "came alive" and looked "elated" as his patients went into respiratory arrest.

Geen even "boasted" about the regular action during his shifts and told one doctor: "There is always a resuscitation when I'm on duty."

One nurse came to court to tell how Geen said: "Oh no, here we go again," as murder victim Mr Bateman turned blue and began to fight for breath.

Geen used different drugs on his victims, including insulin, muscle relaxants and sedatives - all commonly used in the hospital and readily available in emergencies, but "deadly in the wrong hands".

Eventually, after an alcoholic was admitted with stomach pains and ended up in intensive care, doctors decided something was seriously wrong and launched the investigation that led them to Geen.

He was arrested as he arrived for work the next day - with a full syringe of vecuronium, a muscle relaxant, in his pocket.

During his closing speech, prosecutor Michael Austin-Smith QC told the jury Geen must have known the potentially fatal consequences of what he was doing but said that toying with patients' lives was a "price he was willing to pay in order to satisfy his perverse needs".

He said: "People were at death's door. Most were lucky - two were not.

"And on February 9 when Geen went back to work with that loaded syringe, was there somebody else who was extremely lucky that the authorities had nailed their man?"

There is little in Geen's past to suggest what brought him to his murderous present.

From an affluent family, Geen was educated at the Radcliffe School in Wolverton, Milton Keynes, before joining a three-year nursing training course at Buckinghamshire Chilterns University College in November, 1999.

In November, 2002, he qualified as a Healthcare Assistant, and on April 7, 2003, he was appointed as a staff nurse at the Horton General Hospital.

He also served in the Territorial Army, and was a infantryman in the Green Jackets before being made second lieutenant.

When police raided his house after his arrest and found unauthorised prescribed drugs, he told them they were for his military kit.

Mr Austin-Smith told the judge that recommendations have been made within the Oxford Radcliffe Hospitals NHS Trust "on a range of matters".

These, he said, "include the quality of handwriting to the recording of dates, disposing of unused drugs and also a system of reporting (has been) introduced whereby people concerned about matters can have a way of bringing these matters to the attention of authorities".

The trust itself released a statement saying that the safety of patients was "of paramount importance".

It said: "Nurses are put in a position of trust, which includes having access to the drugs used in their departments, and it is particularly distressing when this trust is abused."

One of Geen's victims, divorced father-of-two Robert Robinson, now 53, stressed that he bore the hospital no ill will.

Mr Robinson, who worked for Thames Valley Police as a Pc for 15 years and served in the RAF before that, said: "I found they were absolutely marvellous."

But of Geen, he said: "I just can't understand whatever possessed him to do what he did. He had so much to look forward to and at the tender age of 25 he's lost everything."