Dozens of homes and businesses in St Neots are now without electricity as engineers work to use restore power.
UK Power Networks, which is responsible for the region’s electrical infrastructure, said the fault was reported at about 12.30pm and that around 391 properties were affected earlier today (Friday).
Since the fault was identified that number has reduced to 86 properties.
A statement on its website said: “An underground electricity cable has faulted on our high voltage network, causing an area wide power cut.”
Power is likely to be restored by 5pm at the latest.
Postcodes affected by the outage: PE18 2.