It is the last tree left in Blind Lane, but Peterborough City Council has decided it must be removed as the roots would cause structural damage to nearby houses.
Ollie Bullen, 28, an XR activist who protested under the tree, said on Wednesday: “The council issued an order today to make the land around the tree private.
“That allowed them to call in security and the police to block public access to the highway.
“This morning we were on the scene and held out for five hours before receiving a warning for arrest and being forced to move.”
Ed Murphy, a local resident, said: “People are outraged and desperate to save this 600-year-old tree.
“It has not been proven to cause damage to other homes.
“We need a court order, but I don’t think it’s going to happen.”