A predator raped and sexually assaulted four girls over a seven-year period – one as young as eight.
James Barrett attacked his four victims during a campaign of abuse, which also included making them watch sex acts.
The assaults took place at the 65-year-old’s home and at an address in Bexley, south east London.
Police say he was known to all of his victims.
The victims first contacted police on May 29 and Barrett was arrested and charged the following day, but he denied the charges.
After a five day trial Barrett, of Greenhithe, Kent, was found guilty at Woolwich Crown Court and jailed for 24 years on Thursday.
He was found guilty of 19 charges of sex offences against young girls including five counts of assault by penetration of a child under 13 years, three counts of sexual assault of a child under 13, two counts of rape, four counts of sexual activity with a child, four counts of causing a child to watch a sexual act, and one count of raping a child under 13 years.
The abuse of the four children was committed between 2008 and 2016, while they were aged between eight and 15 years old.
Detective Constable Marie Hill, from the Met’s Child Abuse & Sexual Offences Command, said: “I would like to thank the brave victims for coming forward and pursuing this case.
“This lengthy sentence demonstrates the destructive path this defendant created for these victims and I hope it brings them some closure.”
Detective Sergeant Jivan Saib added: “I hope this conviction for historical offences demonstrates how hard the Met will work to bring justice for victims of sexual offences.
“I hope this encourages all victims of sexual abuse crimes to come forward.”