A young woman, who died alongside her boyfriend following a car crash, may have fallen asleep at the wheel, an inquest has heard.

Sarah Delf and Oliver Appleby, both 24 and who lived on Dereham Road in Norwich, had been together for five years after meeting at the University of East Anglia.

The couple, pictured inset, died at the scene of the crash at Brome, near Diss, on November 15 last year.

An inquest in Bury St Edmunds yesterday heard how Miss Delf's Mazda 2 was travelling towards Norwich when it was involved in a head-on crash with a lorry at around 8.20pm – the lorry driver sustained minor injuries.

PC Andy Fossey, a forensic collision investigator, said there were no defects found with the car or lorry and both drivers were not under the influence of alcohol. The pair were described as 'inseparable' by Mr Appleby's family in a tribute released after the accident.

They had left Margate in Kent, where Mr Appleby's family lives, at around 5.15pm on the afternoon of the accident

The inquest heard Miss Delf, who grew up in the Great Yarmouth area and who was due to complete her PhD this year, had been out the night before the accident and did not get back until 4am.

PC Fossey said a sleep expert who the police consult listed a number of things someone would do if they had fallen asleep at the wheel.

Miss Delf's car had drifted into the opposite lane and there were no skid marks or avoidance manoeuvres, PC Fossey said.

A witness driving behind Miss Delf's car said the lorry driver tried to avoid hitting the Mazda.

'In my opinion there are factors that relate to the incident that Miss Delf fell asleep at the wheel,' PC Fossey said.

'Or it could have been an unknown distraction. There are a number of possible reasons why the Mazda drifted into the path of the other vehicle but the actual cause of the collision cannot be ascertained.'

Miss Delf's family remembered her as being 'beautiful in every sense of the word' in a previously released tribute, adding she 'loved life, and lived hers to the full'.

Mr Appleby was described as 'a bright, enthusiastic young man with a heart of gold' who 'always put others first and doted on his beautiful girlfriend Sarah Delf'. A post-mortem examination revealed the couple died from multiple injuries consistent with a road traffic collision.

The coroner Dr Dan Sharpstone concluded Miss Delf and Mr Appleby died as a result of a road traffic collision.

• The hearing came just a few days after an inquest heard that a highly regarded and popular doctor who died in a head-on collision probably fell asleep as he drove home from the last of three long night shifts at the Norfolk and Norwich University Hospital.

Dr Ronak Patel, 33, had been talking to his wife using a hands-free mobile phone shortly before the crash and the couple had been singing to help him stay awake.

His VW Golf collided head-on with a lorry on the A1088 Ixworth Road at Honington shortly before 9am on August 3 last year and his car ended up partly in a ditch.