Initial survey shows three 'anomalies' around 26 feet underground, but people nearby are told there is no immediate risk.
The specialist unexploded ordnance firm 6 Alpha Associates is surveying the field near Wellington Clos in the Foulon.
It is suspected that three Allied WW2 bombs were dropped there by aircraft returning from a raid on Brest in March 1941.
They may have been sizeable weapons that had to be discarded before the planes attempted to land back in Britain.
An initial survey in 2019 did not find anything but the latest examination has discovered three objects around eight metres below ground.
Until the survey is complete and the data analysed, it is not possible to say with certainty that they are the bombs.

Local ordnance expert Ben Remfrey has indicated that if they are found, they will need to be deactivated and this could involve cordoning off the area, depending on how easy it is to remove the fuses.
The Home Affairs Committee, which commissioned the survey, says people living nearby are not at risk at present because of the depth of the devices.
It is keeping up a regular dialogue with neighbours.
Recently, around 20,000 thousand people had to be evacuated from Cologne city centre in Germany, after three bombs discovered during road construction had to be made safe.

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