A DEAD slug was the cause behind trails of traffic stuck in two-hour long queues around a retail park.

Frustrated drivers were left in ‘car park chaos’ this week due to malfunctioning traffic lights at the Beehive Business Park in Ulverston.

One driver was sat in the car park for more than two hours, describing the hold up as ‘absolute carnage’.

Only four cars were reportedly able to drive out of the park at a time due to a fault with the sensor which detects vehicles at the lights.

Drivers said there were four minutes between traffic lights changing green and only remained so for around eight seconds.

Police officers assisted with traffic management at the shopping park which is said to have caused a hold-up for drivers since the weekend.

National Highways have since revealed that the cause behind the traffic nightmare was a dead slug which had climbed onto one of the sensors and disrupted the movement detectors in the lights.

A spokesman said: “We arranged an engineer to attend as soon as we could.

“We then had to monitor the lights to diagnose the fault which was discovered to be an obstruction issue with one of the sensors which detects movement/vehicles at the lights.

“The obstruction was actually a dead slug which had climbed onto a sensor.

“All the sensors were cleaned and tested and the system is now working normally.

“We’d like to thank road users for their patience on Monday as we worked to diagnose the issue.”

Fears have been raised that traffic chaos may worsen following the opening of Greggs drive-thru in the park later this year.

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The shopping park currently houses Aldi, M&S Food Hall and Screwfix.

Plans to open a Greggs, which were given the green light in February, will include a drive-thru lane and parking for 16 cars, including three disabled spaces.

The plans state the drive-thru Greggs will be open from 6.30am until 8pm from Monday to Saturday, and 8am until 6pm on Sunday and Bank Holidays.

It is expected that Greggs will provide 20 jobs (two full-time and 18 part-time), according to the plans.