The young men are on the roof of a solicitors office in Wrexham.
The firm says they have had to close their office due to the 'stand off', which otherwise has no connection to them.
It says the men have been there since midday on Wednesday, it is liaising with police, and hopes the situation is resolved as soon as possible.
A man who works locally has told ITV News there are a lot of police present in the area, trying to negotiate with the young men, who are throwing objects from the roof.
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Variable cloud and clear spells overnight with isolated showers mainly in the north.
Becoming drier and brighter from the northwest during the day, but with the risk of scattered, locally heavy, showers developing later.