Broadcaster Jeremy Vine has been stopped by police in London's Hyde Park for speeding on his bicycle.
The BBC Radio 2 presenter said he had been caught travelling at 16mph (25km/h) in a 5mph (8km/h) zone.
He apologised after an officer tracked his speed using a radar gun, but seemed not to agree with the speed limit.
"If cyclists are forced to travel at walking pace, they will return to the roads and mix it with trucks," 49-year-old Vine tweeted.
He posted a short film of what happened using the aptly named social media app Vine.
He added in a tweet: "When I got to the office @BBCRadio2 and said I was radar-gunned at 16mph on my bicycle, producer said: YOU ARE LIVING ON THE EDGE."
Vine, who has presented the lunchtime show on Radio 2 for more than a decade, is the older brother of the Perrier award-winning comedian Tim Vine.