As if yet more proof were needed that talking on a mobile while behind the wheel impairs your concentration, this hilarious image has emerged, showing a van driver chatting away on the phone, completely oblivious to a vehicle full of police in front of him.
Despite the van displaying full police livery and the officers inside clearly visible thanks to their fluorescent jackets, the driver remains in his own little world, happily chatting away.
It wasn't until the astonished policeman at the rear of the van tapped loudly on his window, that the van driver realised his foolishness and sheepishly put his phone down.
The image was captured by construction worker Dave Wood, who was sat in the passenger seat of an adjacent van as a queue formed at traffic lights near Heathrow airport.
Speaking to the Daily Mail, he said: "I couldn't believe it. We stopped at lights near this police van full of officers in high-vis jackets when this guy pulled up next to us.
"He was chatting away on his phone, completely oblivious to the fact he was sat behind a minivan full of cops.
"When he finally noticed he had been spotted, one of the officers tapped on the back window and indicated that he pull over."
"He was behind the police van at the lights for about a minute before he noticed. What a fool."
Despite being illegal for a decade, thousands of motorists are still caught each year talking into hand-held mobile phones, and face a fine and three penalty points.
However, it is not known what punishment, if any, this dozy van driver received.