MPs have called for police and mountain rescue teams to search Pendle Hill for unexploded World War Two bombs after a walker found a device on farmland.The man, believed to be from the Clitheroe area, discovered the ‘two-inch high explosive’ mortar while out walking on Saturday.

He only raised the alarm at noon following day and an army bomb squad was called to the scene in Sabden.

Royal Logistics Corps bomb experts attended and sealed off the immediate area as two technicians wired up the unexploded ordinance, believed to date from the 1940s, for a safe detonation.

The device is thought to have been uncovered in the recent wet weather.

Pendle MP Andrew Stephenson said: “I would call on the police and mountain rescue teams to work together to search the area to make sure that no other devices have been unearthed by the bad weather.

“It’s a big safety concern and we need to make sure that Pendle Hill is safe.

“I’m sure that between the organisations they can come up with a plan to sweep the area and rule out this happening again.

“I recently took part in a training exercise with the mountain rescue team and I’m sure they would be able to conduct a search of the area.”

Ribble Valley MP Nigel Evans said: “I think that the police should conduct a sweep of the area just to make sure that no others have reached the surface after the recent bad weather.

“People have to be careful and they should report any item that looks suspicious.

“This is obviously a rare event and I’ve never come across something like this in all my 21 years as MP.

“We need to make sure that the area is safe and that no-one is put off coming to the Ribble Valley.”

In May 2008, bomb disposal experts collected an unexploded bomb from a Ribble Valley village.

A police car was seen escorting the army vehicle towards the fells at Chipping.

The area, which was private land, was used as a training range between the two world wars.

Historian Roger Frost, from Burnley, said: “Pendle Hill was used extensively during the war for training purposes and I would not be surprised if there are a lot more up there.

“The army took over the area at the start of the 1960s and conducted a sweep to attempt to remove any devices that had been left behind.

“They are highly dangerous and even more so if they are picked up and carried around.

“They were used a lot during training exercises on Pendle Hill and a lot more could have been uncovered by the recent bad weather.”

The bomb was found in a field belonging to Rattenclough Farm in Wesley Street and police invited Sabden resident, Xanthe Gill, the niece of the owners, to detonate the mortar.

The 24-year-old said: “It was all a bit exciting and I don’t think many people really realised how big the explosion was going to be.

“It was very cool to be asked to press the button and I’m glad that it didn’t hurt anybody.

“I think that others have been found in the area before but this is certainly the first in my lifetime.

“No-one had any idea that it was there and the recent bad weather must have brought it to the surface.”

The controlled explosion was safely carried out at around 4.30pm on Sunday.

A police spokeswoman said officers were not planning to cordon off any of the hill area to carry out searches but said anyone who came across anything suspicious should not approach it but contact police.

She said: “An officer at the scene said that extreme weather could have caused the device to be unearthed.

“A controlled explosion was carried out a few hours after we received the call.”