Two pilots are being treated for minor injuries following a crash involving an RAF training aircraft.
Emergency services were called to the Pencarnisiog area on Wednesday lunchtime and police are urging the public to avoid the area until further notice.
The Royal Air Force has confirmed it's investigating an incident involving an RAF T2 Hawk jet flying out of RAF Valley.
Training involving the fighter jets has been temporarily suspended as a precautionary measure.
Both pilots were taken by air ambulance to the Queen Elizabeth Hospital in Birmingham, home of the Royal Centre for Defense Medicine (RCDM).
A North Wales Police spokesperson said there are no reports of any wider damage or injuries at this stage.
North Wales Fire Service says the fire involving the aircraft is now "under control" and urging members of the public of the area to avoid the area "while emergency services continue their work safely".
The Welsh Air Ambulance and the Welsh Ambulance Service are also attending the scene.
Train services between Holyhead and Bangor were also disrupted for a time due to "an obstruction on the track", but they have now resumed.
Defence Secretary Wes Streeting posted on X that an investigation into the crash is underway, adding: "My thoughts are first and foremost with the pilots. We will provide further updates in due course."
First Minister, Rhun ap Iorwerth, said he was "very pleased and relieved" to hear the jet's crew were not seriously injured and wished "a swift recovery".
Llinos Medi, Plaid Cymru MP for Ynys Môn, said she was aware of the "serious incident", adding: "I sincerely hope that everyone involved is safe and well."
"I want to extend my deep gratitude to all of our emergency services and first responders who reacted so quickly to the scene."


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