An urgent warning has been issued to dog walkers after an "unknown substance" was found at an Anglesey beauty spot. Environment officers are investigating the incident at Newborough Forest. A Natural Resources Wales statement said: "We’ve received reports of an unknown substance at Newborough forest.

Our officers are investigating and we have informed the police as a precaution. "If you are visiting the forest please be vigilant. We recommend keeping dogs on leads for the time being.

" An image released by the agency showed a number of pink capsules scattered on the ground in the woodland. READ MORE: Storm Lilian updates: trees down, roads blocked and flood alerts as North Wales hit by gales READ MORE: Major emergency response to Pontcysyllte Aqueduct incident as surrounding roads closed Separately, concerns were raised earlier this month over the amount of visitors to the area, with more expected this bank holiday weekend. Last week North Wales Live readers gave their take on the recent gridlock that took over Anglesey .

Visitors trying to reach Newborough’s beach, forest and photogenic Ynys Llanddwyn were left stewing in cars as temperatures rose. The narrow, mile-long access road to the forest was reported to be rammed and locals said queues on the A4080 stretched half-a-mile from the village. Locals and visitors alike are feeling frustrated, igniting an ongoing conversation about the impacts of tourism, the state of infrastructure, and local management practices.

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