Advocacy groups coordinated demonstrations last week against hydraulic fracturing plans from shale pioneer Cuadrilla Resources.
Cuadrilla last year witnessed rowdy demonstrations in the southern British village of Balcombe. The company's exploratory drilling program led demonstrators to believe hydraulic fracturing, or fracking, would be next for the site.
The group No Dash for Gas said Monday three protesters had barricaded themselves inside the gates of a fracking site and two are super-glued together outside the gates.
"Security guards have used brutal and disproportionate force [against demonstrators]," the group said in a statement.
West Sussex police last year said they were frustrated with "the criminal activities" of some of the protest groups, including No Dash for Gas, during Balcombe protests.
Hannah Jones, a campaign director from anti-fracking group Reclaim the Power, said fracking is a dangerous drilling practice that will keep the nation's economy tied to fossil fuels.
"When governments won't act in the public interest, it's up to the public to take action," she said.