It's emerged accidental damage to fibre cables led to thousands of Anglesey residents losing broadband access.
It's believed around 6,000 Openreach customers were affected by the outage for over 24 hours on Sunday and Monday.
The telecommuncations firm has apologised for the disruption caused and says services were restored by Monday evening.
An Openreach spokesperson said: "While installing new poles, we accidentally damaged some fibre cables. We got straight to work repairing the cables and customers were back up and running on Monday evening. Thanks to everyone for your patience."
Earlier, the Plaid Cymru MP for Ynys Môn said she had been told a fault on the network line serving the area was affecting several parts of Anglesey.
Llinos Medi added: "I am aware that this disruption is causing significant issues and frustration for residents, vulnerable customers and local businesses who rely on a stable internet connection."
In August this year, Openreach said full fibre broadband was now available to over 30,000 homes and businesses on the island following a £9 million investment.
But they warned many people were yet to benefit from the upgrade because they could be using slower, less reliable connections.
Martin Williams, Openreach's partnership directof for Wales, said at the time: "Most of Anglesey is now covered by Full Fibre, but many residents and businesses still haven’t made the switch. It’s not automatic – you need to place an order with your chosen broadband provider."
"The difference in speed and reliability can be significant, especially for busy households or people working from home. We want to make sure everyone knows what’s available and how to get it."
"Openreach is committed to building the best Full Fibre network, and doing it sustainably. Through our Let’s Reach Zero strategy, we’re working to reduce carbon emissions, use fewer resources, cut waste, and protect nature wherever we operate."


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