Questions have been raised after a huge police convoy was spotted travelling through Kent last night.
Shocked motorists on the M25 spotted the enormous fleet of cars and vans which appeared to be escorting a truck carrying a huge, covered object.
Watch: the mysterious transport and police convoy
The convoy, which also appears to include Highways vehicles, is thought to have been first picked up leaving Kent into Essex.
One eyewitness who picked the trail up around Junction 30, near Thurrock in Essex, said that vehicles were stopped from overtaking immediately.
"There must have been hundreds of police officers overall, every junction had two van loads join as it passed.
"I was stuck behind it for an hour because they were only letting one car past at a time so it took ages to pass.
"I joined it at Junction 30 but I'm sure it came from Kent. They were transporting a massive lorry, really big with a number of wheels."
After a video was posted to social media showing the convoy, internet sleuths tried their best to work out what the vehicle had been carrying.
The cylindrical object was covered in tarpauline, and many guessed that it was extremely heavy given the size of the transport.
Several guesses included a secure transport of gold, while others wondered if it was nuclear material.
The eyewitness, who asked to remain nameless, said: "I'm guessing it was nuclear material of some sort with hazmat teams driving in convoy, some people have suggested gold but that is moved a lot more discreetly."
Police have been contacted for comment.
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