A 10-year-old Finnish boy has won US$10,000 after hacking photo-sharing app Instagram.
He exposed a major flaw in the social media app when he figured out how to delete any Instagram user's comments and captions, even Justin Bieber's.
"I would have been able to eliminate anyone, even Justin Bieber," he told Finnish news site Iltalehti.
Jani (whose last name is not revealed) proved his ability with Instagram staff, by deleting a comment on a test account.
He was not punished for the hack, but given US$10,000 as part of Facebook's Bug Bounty programme.
Facebook bought Instagram in 2012, making Jani eligible for the cash reward that Facebook gives to people who find flaws in its digital products.
The boy and his twin brother have poked holes in a number of secured websites before, although this is the first time there's been a reward for it.
"We recognise and reward security researchers who help us to keep people safe by reporting vulnerabilities in our services. Monetary bounties for such reports are entirely at Facebook's discretion, based on risk, impact and other factors," Facebook's website says.
Finland is an international leader in technology. The small European country produced mobile phone giant Nokia.