This depends on where the squatters are living.
Squatting in a residential building (like a house or flat) is illegal and the police can use force to enter a property and remove any trespassers. Anyone guilty of squatting can also face up to six months in prison and a £5,000 fine.
Nevertheless, squatting in a commercial property (or any other non-residential property) is not illegal, but it is a crime to damage the building or land. This includes theft, fly-tipping and any damage caused by entering the property or whilst in it. It’s also a crime if squatters stay in the property even after they’ve been told to leave by a court.