The family of one of Britain's most notorious killers who slayed a family with a 4ft iron bar have paid their respects at his funeral today - along with hundreds of campaigners who insist that he is innocent. David Morris, 59, always denied murdering Mandy Power, 24, her bed-ridden 80-year-old mother Doris Dawson and her two young daughters Katie, 10, and Emily, eight, who were bludgeoned to death at their home in the village of Clydach, near Swansea, before the house was set alight. Morris, who said he had been an occasional lover to Ms Power, was found guilty following a trial at Swansea Crown Court in 2002 but the verdict was later quashed. He was again found guilty at a retrial held at Newport Crown Court in 2006 and at the time of his death had spent 22 years behind bars. Morris, known as Dai, mysteriously died on August 20 at Long Lartin prison, Worcestershire, where he was serving a minimum of 32 years. More than 200 mourners, including family, friends and members of the Free Dai Morris campaign attended his funeral today. Relatives and campaigners say they will continue to fight to prove his innocence. Former solicitor John Morris had previously written a book called Clydach Murders: A Miscarriage of Justice, arguing that Morris was innocent and claiming there was no forensic or DNA evidence linking him to the crime. It claims he was convicted because he did not have a solid alibi, his gold chain was found at the Powers' house and he had initially lied to the police, having previously been in trouble for minor offences. Pictured: The funeral cortege, led by horses, arrives at Llanelli Crematorium, Wales, Wednesday 15 September 2021 Janiene Morris (centre with red hair), one of the two daughters of David Morris, is embraced as she arrives at Llanelli Crematorium, Wales The coffin of David Morris being loaded onto a hearse in Swansea, Wales. Morris, 59, killed three generations of the same family in the Swansea Valley village in 1999 The coffin of David Morris is led into Llanelli Crematorium, Wales, Wednesday 15 September 2021 The funeral cortege, led by horses, arrives at Llanelli Crematorium, Wales. Morris, 59, known as Dai, mysteriously died at Long Lartin prison, Worcestershire, where he was serving a minimum of 32 years David Morris, left, always denied murdering Mandy Power (right), 24, and her two young daughters Katie, 10, and Emily, eight, at their home in the village of Clydach, near Swansea. He was found guilty following a trial at Swansea Crown Court in 2002 but the verdict was later quashed. Morris was again found guilty at a retrial held at Newport Crown Court in 2006 and at the time of his death had spent 22 years behind bars After a short service at a relative's home in Swansea, a hearse with flowers saying 'son' and 'Daddy' drove his wicker coffin to Llanelli crematorium. For the final part of the journey the funeral procession was led by two mounted black horses. The location of his wake was kept secret over fears it could lead to protests and violence. Morris had been arrested after the finger of suspicion wrongly pointed to Ms Power's lover, former policewoman Alison Lewis. Cellular material from Mandy Power's thigh was found to match a DNA sample volunteered by her lover, and DNA material from Ms Lewis was also found on a vibrator that had been inserted into Ms Power's body after death. Ms Lewis and her former husband Stephen, an officer with South Wales Police, were arrested on suspicion of murder a year after the deaths, and Mr Lewis's brother Stuart, also a police officer, was arrested on suspicion of perverting the course of justice. They were all released without charge. In 2006, prosecutor Patrick Harrington QC had said Ms Lewis and Ms Power had three 'protracted sex sessions together' and 'the sex aid was used as a device as part of the couple's loving relationship'. He said that any DNA material left on the vibrator was as a result of this activity. In 2001 investigations into the murders were reignited after an off-duty police officer claimed they overheard a conversation about Morris and Ms Power having had sex, leading to Morris becoming the focus of the investigations. He had previously given a statement to police in the weeks after the deaths. Morris was found to have lied about whether a gold chain found at 9 Kelvin Road was his - he swore it wasn't 'on the lives of my children' but later admitted it was. He claimed he had hidden his relationship with Ms Power from police as it would have meant the end of his relationship with girlfriend Mandy Jewell, who had been best friends with Ms Power. Problems were also found in Morris's alibi - he had claimed he wandered the streets for hours after leaving the New Inn pub on the edge of the village of Clydach before getting home at 3am when Ms Jewell let him in. Ms Jewell told police he got home between 10.30pm and 11pm but she didn't let him in - later in court she said she didn't know what time he'd got back but she had let him in. The juries of both of Morris's trials, in 2002 and 2006, were told of his previous convictions for violence. He was found guilty of the four murders at both trials. The Clydach inquiry was the largest and most complex murder investigation ever undertaken by a Welsh police force. Worcestershire's assistant coroner, Nicholas Lane told an inquest opening on August 27: 'Morris was a serving prisoner at Long Lartin prison and it is here that he died. Debra Thomas, the sister of David Morris at Llanelli Crematorium. The location of his wake was kept secret over fears it could lead to protests and violence Morris was again found guilty at a retrial held at Newport Crown Court in 2006 and at the time of his death had spent 22 years behind bars (pictured: A floral tribute by the coffin of David Morris as it departs from Swansea) After a short service at a relative's home in Swansea, a hearse with flowers saying 'son' and 'Daddy' drove his wicker coffin to Llanelli crematorium An onlooker outside the crematorium said: 'It is a big turn out for a man who killed four people including two young girls' Doris Dawson, left, and Mandy Power, right, who were beaten to death. A Change.org petition demanding Morris's case be re-examined 'by an outside police force' with a 'review of the DNA evidence so far not examined' has brought in more than 6,000 signatures Pictured: Katie, 10 (left) and Emily 8. Morris was found guilty at a retrial held at Newport Crown Court in 2006 and at the time of his death had spent 22 years behind bars 'He came out of his cell and collapsed early in the morning and despite attempts at resuscitation, he was confirmed dead at 8.43am on his wing block. 'A post mortem has taken place and as of yet, the cause of death is inconclusive.' Toxicology tests will now take place in an attempt to determine the cause of Morris's death. A full inquest in front of a jury is expected to be held next year. An onlooker outside the crematorium said: 'It is a big turn out for a man who killed four people including two young girls. 'It happened more than 20 years ago but feelings still run high and Morris's death has brought it all back into people's thoughts.' A Change.org petition demanding Morris's case be re-examined 'by an outside police force' with a 'review of the DNA evidence so far not examined' has brought in more than 6,000 signatures. All rights reserved for this news site (dailymail) and under his responsibility