The car was pulled over west of London on Good Friday (local time) with its hazard lights on.
Police tweeted a photo of the BMW complete with a shed strapped to its roof.
“Making a 30-mile (48-kilometre) journey at 30mph (48km/h), with hazards on to warn people of the danger? - Erm... No!” police tweeted.
Police reminded drivers to not only make sure the vehicle they were using was suitable for moving goods, but to also make sure they were properly secured.
People unimpressed by 'unbelievable' driver
Twitter users were left shaking their heads at the driver’s actions.
“Would have loved to have heard the exchange between the officer and driver,” one woman tweeted.
One man called it “unbelievable”, while another person expressed their disbelief, saying: "What a muppet!"
“Does this driver possess a brain?” another woman tweeted.
In responding to the importance of securing loads safely, police referred to another incident shared on Twitter by nearby Gloucester police.
Gloucester police shared a photo of a Nissan with fence panels impaling a windscreen, adding it was “a lucky escape” for the driver.
Police added the driver who had the fence panels was fined for carrying an “insecure load”.
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