On Saturday evening, North Wales Police were called to investigate after several people reported seeing a bright green light in the sky over Caernarfon.
Officers tweeted just after 8 p.m. to say they were responding to calls from worried townspeople about the lights in the sky.
The illuminations were part of what organizers described as “a secure Covid interactive laser event”.
The laser shone from Cilgwyn towards Caernarfon and onto Carmel.
The event allowed anyone who could see the laser and have internet access to control it through a website.
Posting on the Caernarfon Noticeboard Facebook group, Rob Stanley, who organized the event, confirmed that the Civil Aviation Authority had granted the clearance and that local police had been notified.
Organizers expected the light to reach Caernarfon but some people commented saying they could see it as far as Beaumaris on Anglesey and others said they could see it from Bangor.
The event turned out to be popular with some people having to queue for 40 minutes to access the website itself before being given 60 seconds to control the laser.
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