About a dozen people, including policemen, were injured here on Monday when police used force to free a plot from encroachment, officials said.The Ghaziabad Development Authority (GDA) sought police help to get a 2,012-square metre plot freed from encroachers after a crowd began pelting stones at a bulldozer and GDA employees."Finding no other option, police used force against the mob," police officer Randhir Singh said.The plot was allotted to a builder who wanted to start construction. "The GDA was bound to hand it over to him encroachment-free," he added.