A newsagent said he felt "real emotion" when he received a £10 note and a handwritten letter from a former shoplifter apologising for their actions.
Halil Kurt owns two shops in Weston Park, Crouch End, popular with students from nearby Hornsey Girls School.
Halil said he was standing outside the branch of Londis he runs on May 17 when he saw a student walk in to his other store, Weston Off Licence, four doors down.
He walked over to see if they needed any help but when he got there the student had gone but a letter had been left on the counter.
Inside he found an anonymous letter containing £10 and a heartfelt apology for stealing ice cream many years earlier when they were "significantly younger".
"It was quite emotional," said the dad-of-three. "As I read the letter I was just like happy, that kind of thing... it made me happy that someone is still doing what's supposed to be done even though they made a mistake in the past."
The letter writer wrote: "I am writing this letter to apologise for my actions of shoplifting from your store.
"I want to take full reponsibility for my actions and I am deeply sorry for the inconvenience that I have caused."
The writer assured Kurt that they had learned their lesson and would "never shoplift again".
They added: "I have enclosed £10 to compensate for my actions and the goods that I took. I hope you can forgive me sincerely."
Kurt said: "I felt real emotion. It was something that I wasn't expecting."
He said he looked at his CCTV footage and saw that it was a student who left the letter but did not know if it was delivered on behalf of someone else.
"All these students come into my shop every day and I'm always friendly with them.
"I give them sweets sometimes if they don't have money. I'm like an uncle but they have to follow the rules.
"If people do something like this and they pay it back I am the happiest person in the world."
David Winskill, who lives nearby, said: "It's clear that this has been playing on the mind of someone, possibly for decades.
"The sense of relief they are feeling is wonderful. It's really brought a lot of joy to people who have heard about this in that having a conscience still exists in a lot of people."
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