Two konectbuses have been snapped within 15 minutes of each other with so much dirt covering the back of the buses that the lights and number plate are barely visible.
The first bus, route 51, was photographed at 12.15pm on Saturday on Prince of Wales Road.
The bus lights were covered in dirt and the number plate couldn't even be seen.
A second bus, route X7, was caught on camera just 15 minutes later on the A47 towards Yarmouth, near County Hall, in a similar grubby condition.
It is an offence to drive with a dirty number plate and can be punished with a fine up to £1,000.
Earlier this week, a police car was photographed with dirt covering the number plate in Wisbech.On the same day, police in Ely fined a motorist £100 for the same offence.
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