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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It will be very mild, with early cloud lifting and breaking to allow warm sunny spells by late morning.
Rather breezy, but dry and unseasonably warm, with early cloud soon breaking to give some good sunny spells.
Mild and cloudy outlook.