Friends of a car enthusiast and his girlfriend who were found dead inside a vehicle have made a tribute video inspired by Hollywood blockbuster Fast and Furious.

Motor apprentice Tom Putt, 20, was found slumped in the blue Ford Focus yesterday alongside shop worker Nikki Willis, 23, who is believed to be his girlfriend.

Police said their deaths were being treated as 'unexplained' and there were concerns yesterday over 'noxious substances' found inside the vehicle, which was parked outside Miss Willis's house in Chelmsford, Essex.

Witnesses described hearing a loud bang moments before the bodies were discovered, with one neighbour likening the noise to 'a can exploding'.

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Tragic: Shop worker Nikki Willis, 23, left, was found slumped in the blue Ford Focus alongside motor apprentice Tom Putt, also in his 20s, right, who is believed to be her boyfriend

Today friends paid tribute to the couple on social media. One Facebook group called 'Car Society' posted a video today remembering Mr Putt and Miss Willis.

The clip was made up of photos of the couple alongside photographs of cars. They were accompanied by the soundtrack to the most recent Fast and Furious film.

It was shared with the message: 'R.I.P to a young friends who sadly passed away together. Thoughts are with their family and friends.'

It ended with the words: 'Gone but never forgotten'.

On Facebook, Miss Willis's cousin Claire Watts wrote: 'My beautiful baby cousin. There are no words to describe how I'm feeling right now. I still can't believe you have been taken from us – it's a bitter reminder of how cruel life can be. I will never forget you.'

Mr Putt is believed to have been an apprentice with the Ford Motor Company and lived in Leigh-on-Sea, Essex.

Friend Ben Henderson wrote on Facebook: 'My very good friend Tom Putt and Nikki sadly lost their lives today.

'Tom was always there to help me and has been such a good friend to me and always there when I needed him and was a friend that I could always rely on!'

He added: 'You shouldn't take life for granted as you never know what might happen in such a quick space of time. Tom, I am so proud to of known you and had the pleasure of calling you my friend.'

Mr Putt is understood to have been a car enthusiast and had helped others repair and alter their own Ford vehicles.

Police said their deaths were being treated as 'unexplained' and there were concerns yesterday over 'noxious substances' found inside the vehicle. Pictured, the scene yesterday

Witnesses described hearing a loud bang moments before the bodies were discovered, with one neighbour likening the noise to 'a can exploding'. Pictured, the scene yesterday

Locals said they had seen the pair chatting in the car with the engine running outside Miss Willis' home early yesterday morning. Pictured, police at the scene yesterday

Locals said they had seen the pair chatting in the car with the engine running outside Miss Willis' home early yesterday morning.

Miss Willis, who worked for the computer games company CeX, is said to have lived in the house with her mother Michelle Hindson, 46, and stepfather Stuart Hindson, 45.

A woman, who asked not to be named, said: 'I was walking down the road this morning and saw these two people in this blue Ford Focus.

'I didn't think anything about it. The engine was running and they were chatting. The woman was in the passenger seat and the bloke was in the driver's seat.'

Others said they heard a loud bang before the bodies were discovered.

Emergency services were called after a passerby spotted two people slumped over inside the vehicle near Fox Crescent in Chelmsford, Essex. Pictured, the scene yesterday

A hazardous response team was dispatched and a road sealed off as police, fire ambulance crews responded to what was described as a 'chemical incident'. Above, the scene yesterday

One neighbour said: 'I've been at home all day and I thought: "That bang can't be a firework, can it?" It sounded like an exhaust.' Another neighbour likened the noise to 'a can exploding'.

Sarah Bownes, 37, said: 'Someone told me a male and female were found in the car, dead with blue lips. It's a bit scary that it just happened over the road.'

Mutsa Mtangadura, 28, said: 'Literally just now I came to get the bus and a gentleman told me they're not running.

'I saw the police and ambulances around. I was thinking 'what's going on'. That's when he told me what house it was. I worked with the family. It's shocking.'

Last night, the road, where many of the houses are semi-detached and council-owned, was cordoned off and police cars surrounded the Focus, which had been covered with a black tarpaulin.

Tests were conducted to check for potential noxious substances to ensure the safety of emergency services and the public. The scene was later declared safe.

An Essex Fire Service spokesman said: 'Fire crews used detection equipment to test the vehicle for any possible hazardous materials. The investigation is ongoing.'

Essex Police declined to say whether the incident was being treated as a suicide.