An expectant mother was left to give birth to a baby boy on the hard shoulder of the motorway after getting stuck in a traffic jam.
Baby Tommy was born in the back seat of a Vauxhall Zafira on M42 east of Birmingham after the father-to-be made a frantic 999 call just before 5.30pm on Saturday.
Police raced to the scene, but were held up by the five-mile tailback - caused by a fuel spill - and by the time they had run up the hard shoulder the mother was already sat cradling her baby.
Pc Barry, from the Central Motorway Policing Group (CMPG), said: "By the time we arrived mum had done all the hard work and we there to make sure everyone was OK.
"The family were driving home on the motorway and had got caught up in traffic following a diesel spillage.
"The lady, who already has two sons aged two and four - who were in the car at the time, suddenly went into labour which was a complete shock as the baby wasn't due for another three weeks."
Pc Barry said the woman, who has not been named, gave birth to her baby on the back seat of the car, her two older sons next to her and "as happy as Larry that they had a little brother".
He said: "Mum was in a little bit of pain, which is understandable, but everything else was perfect.
"She delivered him all on her own. She was only in labour for 20 or 30 minutes, so she has done really well. She had just finished up when we got there and had gotten him into a blanket."
An ambulance struggled to get through the tailbacks, so Pc Barry and his colleague drove the family's car down the hard shoulder to where paramedics were waiting at the nearby National Motorcycle Museum.
Pc Barry said: "I have only been on the motorway group for eight months. Every day is different but this one is perhaps going to stick in my mind for a while.
"It was lovely to receive a photo of the baby, named Tommy, and we are glad that they are all doing well."