A Royal Mail lorry driver on his first ever nightshift fell asleep at the wheel and killed a grandfather after wasting his sleep breaks to watch videos on his phone, a court has heard.

Stefan-Alexandru Bloj's 44-tonne lorry ploughed into the back of David Sullivan's Citroen van at Redbridge roundabout after the HGV driver allegedly nodded off.

Southampton Crown Court heard Bloj, an agency worker, had only started working for Royal Mail a week before the smash.

He was driving down the M271 in his Mercedes Actros lorry at the end of a 12-hour shift.

Witnesses who saw the horror smash compared it to an 'explosion' that resulted in Mr Sullivan's Citroen Relay flying into the air and the 64-year-old suffering devastating injuries.

READ MORE: Tributes to 'beloved' man who died in M271 crash

Bloj, 34, was meant to have taken rest breaks but instead watched videos on his phone and texted his partner meaning in the 24 hours leading up to the crash he had a total of just five hours sleep, a court heard.

Bloj denies causing death by dangerous driving following the 8.30am crash on November 17, 2020.

Mr Sullivan, a grandfather of six, was sitting stationary in his van in traffic before the roundabout when Bloj's lorry smashed into the back of him.

Bloj was allegedly asleep behind the wheel and hit the van whilst travelling at a speed of less than 40mph.

Daily Echo: Stefan-Alexandru Bloj is charged with causing death by dangerous drivingStefan-Alexandru Bloj is charged with causing death by dangerous driving (Image: Solent News and Photo Agency)

The crash caused a 'domino effect' and two other vehicles, a Nissan Navara and Mercedes Vito van, were caught up in the crash, it was heard.

One driver, David Morris, performed CPR on Mr Sullivan for over ten minutes until paramedics arrived and motorist Thomas Boas said the impact of the crash was so great his glasses came flying off.

Police seized the HGV driver's phone and saw a message to someone sent 25 minutes after the accident saying 'I messed up'.

READ MORE: Driver in court after man dies in M271 crash

Prosecutor Tana Adkin KC told the trial: "David Sullivan was driving a white Citroen Relay Van, south along the M271 towards Southampton.

"The weather was fine, it wasn't raining at the time and the sun had risen, visibility was good and the road surface was dry.

"As the driver approached the Redbridge roundabout, he slowed it down in order to negotiate the roundabout.

"Mr Sullivan was driving a good slow speed and he left a gap between his vehicle and Mr Boas'.

"Mr Boas saw [the lorry] travelling fast towards the Relay van behind him.

"The large road lorry did not stop and hit Mr Sullivan's van, causing it to hoist up into the air and into Mr Boas' vehicle."

Daily Echo: David Sullivan died in a crash on the M271David Sullivan died in a crash on the M271

Detailing Bloj's lack of sleep, the prosecutor added: "The defendant had slept for less than five hours during the 24-hour period prior to the collision.

"He did not sleep in his breaks and he used his time to speak to his partner and use his time to watch videos.

"The defendant, driving through the night, would have known that he did not have enough sleep in the 24 hours."

Giving evidence, Mr Morris, who was driving a Kia Sportage, said the crash was an 'explosion' with 'glass and debris everywhere'.

He told the court: “The traffic was normal and my lane was empty.

“I hung back a little and next thing I know, there was an explosion. There was glass and debris everywhere.

“I immediately pulled over.

“I opened the door to see the condition of the person. It wasn’t good.

“I opened the door and shouted to see if I could get any response.

“I climbed into the van. I wanted to get him out of the van, but this was impossible.

“I continued doing [CPR], carried on shouting for a response but I didn’t get one.”

Married Mr Sullivan leaves behind a wife, two children, three step-children, and six grandchildren.

His family said Mr Sullivan, from Wivelsfield Green, near Lewes, East Sussex, is 'very sorely missed by everyone who knew and loved him'.

Bloj, from Southsea in Portsmouth denies causing death by dangerous driving.

The trial at Southampton Crown Court continues.