Fracking was brought to a halt on Tuesday after seismic activity was detected at a site in Lancashire.

The temporary pause came just over a week after the process began at the Preston New Road site, the first operation to take place in the UK in seven years.

An event measuring 0.4 on the Richter scale was detected, prompting oil and gas company Cuadrilla to call off activity for the day despite being within the limit allowed by UK authorities.

Though the earth tremor was not detectable on the surface, it was the sixth recorded in the area since fracking restarted.

Cuadrilla said it would “adopt extra caution” following the “extremely low level of seismicity” detected at the site, but vowed to start again on Wednesday.

In 2011 fracking was temporarily banned in the UK after experts said two Lancashire tremors – one of which registered a magnitude of 2.3 – were caused by shale gas test drilling.

The most recent tremor registered as an amber event on Cuadrilla’s “traffic light” system for monitoring safety. Firms are required to stop fracking if magnitudes exceed 0.5.

Commenting on its decision to pause fracking, Cuadrilla said: "Seismicity will, as always, continue to be monitored closely around the clock by ourselves and others and we plan to continue hydraulic fracturing again in the morning.

"Local residents should be reassured that the monitoring systems in place are working as they should.

"These are tiny seismic events that are being detected by our monitors as we fracture the shale rock, and are not capable of being felt, much less cause damage or harm."

How fracking works and where it could happen Show all 2 1 /2 How fracking works and where it could happen How fracking works and where it could happen Fracking: How It Works How fracking works and where it could happen Fracking Map UK

Experts noted that Cuadrilla was being very cautious in pausing fracking, and that the small seismic signals were only being detected due to incredibly heavy monitoring at the site.

“There is no evidence to suggest that these tiny earthquakes will lead to larger ones,” said Dr Jessica Johnson, a geophysicist at the University of East Anglia.

The Preston New Road site has seen regular protests since drilling began there again earlier this month.

Opponents of fracking say it can cause water pollution as well as earth tremors, and that investment in new shale gas infrastructure will tie the UK to a future of fossil fuel use.

A spokesman for Frack Free Lancashire said they were “greatly concerned” about the latest seismic events.

"It is most alarming for residents. Considering this is only the exploratory phase and only one frack a day, imagine how much worse it could be.

"The increased risk of larger magnitude quakes is serious. Cuadrilla must stop now, for all our sakes."

Fracking was given the green light in Lancashire after a failed bid for an injunction to prevent shale gas exploration at the site.

Support free-thinking journalism and attend Independent events

The judge said there was no evidence to support local environmental campaigner Bob Dennett’s claim that work at the site posed more than a “medium risk”.

Cuadrilla intends to drill two exploratory wells to establish whether gas extraction at the site is commercially viable.

Fracking has been a contentious topic in the UK, with the government pushing ahead with plans to expand operations despite widespread opposition from the public.

Even Conservative MPs and councillors have expressed concern about the party's support of shale gas, which they say could cost them votes in future elections.