A Harpenden man who subjected his partner and her teenage daughter to a frenzied knife attack has been jailed for more than 13 years.

St Albans Crown Court heard that 46-year-old Gregory Williams, known as “Reggie”, launched an unprovoked attack on the pair in the early hours of December 8. He had been drinking and an argument broke out over the pet dog.

Williams, of Southdown Road, attacked his step-daughter, who was then 18. She received nine stab wounds to her head and neck and two stab wounds to her back. His then partner, who tried to intervene to stop Williams harming her daughter, also received stab wounds to her head, arm and hands. Her younger daughter, 13, ran from the house to escape the violence and called police.

Williams left the home following the attack and drove off in his car before crashing on the M1. Officers found a note on him indicating he wanted respect from his partner’s daughter.

Williams was found guilty of two counts of Section 18 GBH on October 22 following a nine-day trial. He also pleaded guilty to drink driving.

Det Sgt Adam Conder from the Domestic Abuse Investigation and Safeguarding Unit said: “The attack was so quick and frenzied that neither of the victims realised that they had been stabbed – they thought they were being punched.

“Both victims required surgery and have suffered long term injuries. It is likely that the daughter would have been even more seriously hurt had her mother not intervened in the assault.

“The 999 calls from both teenage girls were chilling to hear and I will never forget them. All the victims have shown great courage in dealing with this incredibly traumatic and frightening incident.”

Williams, who had no history of offending, was sentenced to 13 and a half years for each GBH offence to be served concurrently.

Judge Stephen Warner described the incident as a “terrifying ordeal” for the victims in their own home, adding: “The memory will remain with them for many years to come.”

Williams was also banned from driving for 12 months in relation to the drink drive offence.