Two people have been seriously injured in a head-on road smash near Kirk Langley.
Police say a female driver and a male passenger were badly hurt in the accident which happened on the A52 at around 10.10am between Kirk Langley and Brailsford.
The two cars involved were a Volkswagen Golf, carrying three passengers, and a Peugeot 307. The injured motorists were in the Peugeot.
The A52 is still closed in both directions between Kirk Langley and Brailsford, and is likely to remain closed until later today.
An air ambulance also arrived on the scene shortly after 11.30am.
Collision investigators were this afternoon at the scene examining how the accident happened.
Holidaymakers Alan and Linda Johnson of Macclesfield were on their way home in their camper van when they came across the aftermath of the accident.
Mr Johnson, 51, said: "We were heading towards Ashbourne on our way back to Macclesfield and just came to a stop when we got to a line of traffic.
"A few minutes later the air ambulance arrived and was on the ground for quite a while before it took off again.
"There were also two other ambulances. I hope that the people involved are OK."
His wife, Linda, 50, said: "It's a horrible thing to happen and I hope that the people are OK. It's not a great way to finish to our holiday."
Lorry driver Richard Hewitt, 46, was stuck in the queue close to where the accident took place.
He said: "I'm delivering steel to Ashbourne and then Burton and I'd just delivered a load to Kirk Langley when the office informed me there had been an accident.
"As I approached the scene the traffic came to a stop. I saw three fire engines and two ambulances further ahead and then the air ambulance landed.
"I hope no-one has been too seriously hurt but I've been told the road will be shut for a while."
The A52 is closed both ways around Kirk Langley due to a serious accident. This will cause major issues for the swift, please bear with us
— trentbarton live (@trentbartonlive) October 21, 2014RT @AshbourneNews: BREAKING NEWS: A52 closed nr Brailsford because of serious accident http://t.co/1tQF5pqCTX#derbyshire
— Derbyshire Dales DC (@derbyshiredales) October 21, 2014BREAKING NEWS: A52 closed nr Brailsford because of serious accident http://t.co/KFCkMO2hgJ#derbyshire
— News Telegraph (@AshbourneNews) October 21, 2014