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."
More top news
A young boy who was told he would never talk has defied doctors by finding his voice, singing Olly Murs songs.
Cloudier on Monday although it will stay dry.
Turning cloudy in the east overnight. Sunny spells tomorrow.