The UK Border Agency has confirmed the demonstrator on the roof of the Morton Hall centre in Swinderby near Lincoln is a detainee of the immigration centre.
"There is currently a peaceful protest ongoing at Morton Hall in which one detainee has scaled the roof.
"We are working with the Prison Service to resolve the situation."
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A largely cloudy but mostly dry start.
A cloudy or misty start to the weekend, although mainly dry with sunny spells developing. Low cloud may linger in some spots.
A largely cloudy start to the weekend but mostly dry start. Through the day, some sunny spells are likely to develop.