A GP struck off for giving vulnerable elderly people excessively high doses of morphine admitted hastening the deaths of patients in his care, it was reported today.

Dr Howard Martin, 75, of Penmaenmawr, Gwynedd, said in an interview that he gave fatal doses of painkillers to terminally ill patients in a bid to limit their suffering.

The doctor, cleared of murdering three patients, told the Daily Telegraph: "I twice helped people die, not because they wanted to die but because they had such dreadful suffering. Everyone else wanted to (die) - they could make that choice."

Instead of being a second Harold Shipman, Dr Martin said he was motivated by "Christian compassion" and acted in the best interests of his patients.

He said: "I just promised people that they could die free from pain and with dignity.

"Most times patients and relatives were of an accord and wanted the patient to be free from pain and have dignity. In that scenario I would take control by keeping people asleep until they had passed over."

Yesterday, the General Medical Council struck Dr Martin off for his "deliberate course of conduct" towards 18 elderly vulnerable patients who died shortly after he gave them excessively high doses of morphine. The hearing concerned the deaths of the patients between 1994 and 2004.

Dr Martin has not spoken about his actions during the murder trial, inquests into the deaths of the three men or the GMC hearing which ended yesterday, and admitted speaking out about the case may lead to him "spending the rest of my life in prison".

The GMC panel found him guilty of serious misconduct because of his inappropriate and irresponsible painkiller injections and erased him from the medical register.

Dr Martin did not attend the hearing in Manchester as he explained he was not prepared to travel from his home because his wife, aged in her late 80s, was in poor health and he saw no "practical consequences" for him whatever the outcome. He added he was retired and did not wish to work in medicine again.

He was arrested in May 2004 at his practice in Newton Aycliffe, Co Durham, one of his three surgeries, after relatives of an elderly cancer sufferer raised concerns with police after his death. An examination showed high levels of diamorphine in the man's system.

The GMC hearing was told that while some of the 18 patients may have had only days or hours to live, in many cases the General Medical Council panel was told Dr Martin's treatment was "completely unacceptable ... with a real possibility of hastening the death of several".

However, one patient - 74-year-old Harry Gittins - may have gone on to recover from oesophageal cancer had Dr Martin not intervened and administered 200mg of diamorphine on the day before he died.

He went on to tell his family that the cancer spread when there was no truth whatsoever in that statement, the hearing was told.

He was subsequently charged with murdering Mr Gittins, along with Frank Moss, 59, and 74-year-old Stanley Weldon, whose bodies were exhumed at separate cemeteries. He was then accused of their murders, but was acquitted by a jury at Teesside Crown Court in 2005.

In March, an inquest into the three men's deaths found the injections he gave to Mr Moss and Mr Gittins were not clinically justified and contributed to their deaths.

The three men were patients of the doctor when he was a partner at the Jubilee Medical Group which had surgeries in Newton Aycliffe, Shildon and Eldon.

Dr Martin said one of those he had given a final injection to was his son Paul, who suffered from cancer before his death in May 1988, explaining: "What more could I do for him other than make sure he had dignity?"

He added: "On Judgment Day I will have to answer to God, and my answer will be this: that I did my best for my patients."

Dr Martin, who lives in a bungalow in Penmaenmawr, Gwynedd, North Wales, said he feels no guilt or remorse.

He told The Daily Telegraph he wanted a reform of the care system in Britain that does not afford people the "dignity" of dying at home.

He added: "A vet would put a dog down, but under the current system a doctor is not allowed to take positive action to help a patient in a humane way.

"I don't believe I've killed any patients. I believe I've made them comfortable in their hour of need. But I am deemed to be arrogant because I used my discretion.

"They want to extrapolate that to say I'm choosing to kill people. It's not like that. The patients are about to die and I want to make sure they are comfortable.

"How can a so-called caring society not understand that? How can I be reckless with someone who is about to die?"

The GMC hearing was told that three families of Dr Martin's patients remained supportive of him and his treatment of their relative. Others were "neutral", while some were "highly critical".

In finding Dr Martin's fitness to practise impaired, GMC panel chairman Professor Brian Gomes da Costa said: "Dr Martin's decisions to administer large doses of strong painkilling drugs were made on the scantiest of evidence.

"There were many occasions when there was no clinical indication that the patient was suffering any pain. His record keeping, including reasons for giving treatments, was appalling.

"Dr Martin's actions were indicative of an autocratic attitude, in that he seemed always to consider that he was right and rejected, or did not seek, the views of others. He repeatedly broke the trust to which patients are entitled; this is unjustifiable."

Dr Martin qualified in 1957 and was employed as an Army doctor for 18 years before he became a GP in 1977.

Shipman, who killed an estimated 358 people, once worked as a locum at Dr Martin's practice, the newspaper added.