A British arcade center in the around of Liverpool was purportedly defaced with a cheeky bulletin by a group of bearding hackers on May 29, BBC reports.

“We advance you advance your security,” the aggregate wrote on the screen, anecdotic themselves as the “friendly adjacency hackers.”

The autograph appeared on a large alfresco affectation at the Liverpool One arcade center anchored just alfresco of the city. According to reports, no other screens were afflicted – though passers-by said that several other billboards have since been deactivated.

Numerous users on Reddit and Cheep have appear spotting the tampered billboard, but Liverpool One was quick to acknowledge to the spoof, closing down the screen as soon as it was notified about the incident.

It charcoal cryptic who was amenable for the hacking. A agent for the arcade center has since told BBC that the “screens are operated by an alien aggregation [Elonex] which is currently investigating what happened as a matter of urgency.”

“We can affirm an adventure occurred over the weekend on one of the 18 screens we accomplish at Liverpool One,” a agent for Elonex told BBC. “The adventure appears to have been acquiescent and not advised to cause answerability or disruption, for which we are grateful.”

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