Fracking firm Cuadrilla drilling for shale gas in Lancashire
Drilling has begun at a fracking site in Lancashire.
Cuadrilla started drilling a pilot well on Thursday to identify the best locations for shale gas extraction at the Preston New Road site in Little Plumpton.
The pilot well approximately 3,500m (11,500 ft) deep will be followed by two horizontal wells.
Protests have been taking place at the site since work began to prepare for drilling in January.
Francis Egan, chief executive of Cuadrilla, said it is "an important milestone for the energy industry in the UK as well as the community in Lancashire".
Helen Rimmer from campaign group Friends of the Earth said the drilling means "local people will be subject to 24-hour noise, seven days a week, from a fracking project that they don't even want."
As per its agreement with the government, Cuadrilla has put £100,000 into a fund which the local community can use for projects in the area.
Fracking: Shale rock professor says UK gas reserves 'hyped'
The gas reserves in shale rocks in the UK have been "hyped", an academic said.
Professor John Underhill from Heriot-Watt University said the UK's potential shale deposits were likely to have been disrupted by shifts in the earth 55 million years ago.
He said the government would be wise to formulate a Plan B to fracking for future gas supplies.
But the fracking firm Cuadrilla said it would determine how much gas was present from its test drilling.
Hydraulic fracturing, or fracking, is a technique designed to recover gas and oil from shale, a sedimentary rock found worldwide.
The amount of shale gas available in the UK is acknowledged to be a great unknown.
Cuadrilla said estimates from the British Geological Survey (BGS) indicated a large potential gas reserve.
