Police who pulled over a car doing 100mph on the motorway found a woman giving birth in the passenger seat!
Four police cars chased after Colin Ellmore's car on the M275 in Portsmouth.
But when they opened the door on the hard shoulder, they discovered Colin's daughter Tiffany about to deliver her baby.
The 26-year-old's waters broke as Colin, 52, rushed to try and get her to hospital.
And as four unmarked police cars surrounded his Vauxhall Astra, the grandfather explained what was happening - just as the baby's head started coming out.
The officers then helped Colin deliver his 6lb 4oz grand-daughter Lola-Mia Read by the side of the motorway.
Delighted Tiffany - who has three other children with partner Steven Read, 30, - told her local paper: "I started getting contractions at 4pm and I didn't think anything of it.
"It got to 9pm and they started getting really fast, one every five minutes, so I phoned the hospital to say I was coming in and called my dad to pick me and my partner up.
"As I was getting into the front seat of the car I had three contractions within five minutes. I said to my partner 'I really need to push' but he just told me to wait.
"My dad was going 100mph down the M275 when four unmarked police cars suddenly surrounded us.
"I shouted 'My waters have broken'. I didn't know what to do. My dad kept saying 'I cannot stop'.
"When he pulled over the baby's head was already coming out so my dad helped deliver her, which was a nice touch.
"The police officers came round and wrapped Lola-Mia up for me. They were brilliant, they stayed until the ambulance arrived and took us to hospital."
Tiffany, from Portsmouth - who was not due until June 24 - was then taken to the Queen Alexandra Hospital. Both mum and baby were sent home the next day.
Proud dad Steven said: "The whole experience was something like you would see on a television programme. Being in a chase and then Tiffany giving birth was all a bit manic.
"The police said they thought we had stolen a car so they were a bit shocked to find Tiffany in labour. They said they wouldn't give us a speeding ticket because of the circumstances.
"Lola-Mia is doing really well now though and it will definitely be a story we will tell over and over again."