A driver was under the influence of cannabis, using his mobile phone and speeding when he smashed into a crashed car, killing the driver, a court heard.

Convicted drug dealer Ahmed Mohamed, who was about three times over the legal limit for cannabis, had failed to see warning signs and was in the wrong lane on the A2 at Darenth at the time of the crash.

The victim Mark Sharp, from Gravesend, survived two of three collisions in his Nissan Micra - all captured on CCTV cameras - before the 28-year-old labourer and mail sorter came along in the early hours in a rented Nissan Qashqai.

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There was a gap of 14 minutes between the third collision and the fourth fatal crash involving first a Ford Focus driven by Bluewater cleaner Stuart Lomas, 63, and then Mohamed.

Mohamed, of Ann Street, Plumstead, south east London, had denied causing the death of married HGV driver and classic car enthusiast Mr Sharp, 46, by dangerous driving.

But his guilty plea to causing death by careless driving while over the prescribed limit was accepted.

Lomas, of Upper Wickham Lane, Welling, had denied dangerous driving and his guilty plea to careless driving was accepted.

Mohamed was jailed for four years and 11 months and banned from driving for seven years and five-and-a-half months. He will have to take an extended driving test before being allowed back on the road.

Lomas was fined £375 and his licence was endorsed with six points. He was ordered to pay £250 costs.

Maidstone Crown Court was told Mr Sharp’s car was close to an unidentified vehicle on the coast-bound carriageway when at about 5.10am on March 1 last year he collided with the safety barrier and rebounded back into the road and straddled lanes two and three.

Prosecutor Simon Taylor said Mr Sharp put on his hazard lights but it was likely the rear ones were not working.

About 16 seconds later a Citroen Saxo braked to try to avoid the Micra but was unable to do so. The Saxo was then stranded in lane two facing oncoming traffic.

The Micra was pushed further down the carriageway and continued to straddle lanes two and three.

Seven seconds later there was a pile-up involving the Saxo, a Ford transit flatbed, a Mercedes Sprinter, a Citroen C3 and a Mercedes box van. All those involved escaped with minor injuries.

“During the 14 minutes between the third and fourth collisions in excess of 160 vehicles managed to avoid colliding with the Saxo and the Micra, albeit there were some near misses,” said Mr Taylor.

“Multiple calls were made to the emergency services following the first three incidents, including one from the driver of the Micra, Mr Sharp, who provided details of what had taken place.”

The fourth crash which resulted in Mr Sharp’s death from “critical” injuries involved his car, the Saxo, the Focus and the Qashqai.

The Focus, with Lomas on his way to work at Bluewater, was travelling in lane two at an average speed of 48-55mph when he managed to avoid a collision with the Saxo but hit the Micra, making it rotate.

Mohamed’s Qashqai, with a friend in the back seat, approached at an average speed of 70-86mph when he steered to the offside to avoid a collision with the stationary Saxo.

But he then hit the offside of the Micra, causing it to rotate and collide with the central reservation safety barrier. The Micra came to rest across lane three.

The Qashqai overturned and ended up in lane two on its offside facing back towards London.

Police found a cannabis grinder, smelling strongly of the drug, in Mohamed’s car.

Mr Taylor said Mohamed flatly refused to give a blood sample at 10.24am after being taken to hospital, claiming to have a phobia about needles.

"The investigation revealed his mobile telephone was being used immediately prior to the incident. In addition, he was driving too fast, in excess of the speed limit for the road" - Prosecutor Simon Taylor

He agreed to give urine specimens within an hour but failed to do so.

“As time was ticking - and no doubt the defendant knew it - the police decided to call a forensic nurse practitioner to assist in taking samples.”

Mohamed finally agreed to provide a sample and one was taken just after 2pm - eight-and-a-half hours after the collision.

The level of cannabis in blood was 6.4 micrograms per litre of blood. The prescribed limit is two micrograms per litre of blood.

Mr Taylor said examination of Mohamed’s phone showed it was used to place 11 calls and send one text message between 5.02am and 5.24am, which would have required him to physically identify the number to be dialled and press the send button.

The last three calls and the individual IDs used to make them were consistent with the phone being used as it travelled towards the crash site.

Mr Taylor said the gantry warning signs first went on at 5.17am.

Had Mohamed and Lomas adhered to the Highway Code and been driving in lane one, he said, their collisions would have been avoided.

When interviewed, Mohamed thought at the time he had neither driven carelessly nor dangerously.

He said he had used his phone for satellite navigation. His friend was asleep in the back. He explained he was driving in the middle lane “for comfort”.

After the crash his friend helped him out of the car. He injured his shoulder and had cuts to his knees. He said he had not seen any warnings of danger.

“The case against Mr Mohamed is that his driving caused the death of Mr Sharp,” said Mr Taylor. “The very nature of his driving is clear from the CCTV footage.

“However, it was only when the investigations concluded the full depth of his ineptitude was revealed.

“The investigation revealed his mobile telephone was being used immediately prior to the incident. In addition, he was driving too fast, in excess of the speed limit for the road.

“It gave him no chance to avoid a collision. His driving was so poor because he had consumed cannabis. When and how much exactly we cannot say because of the delay in taking a sample at the hospital.”

“It is almost impossible to obtain a precise amount of consumption. He had in his vehicle a cannabis grinder. The inference can be drawn he had consumed cannabis very shortly before getting behind the wheel.”

The court heard Mohammed was given a suspended sentence in 2011 for possessing cocaine with intent to supply. He had further convictions for possessing cannabis in March 2012 and April 2014.

"Nothing I can do, no sentence I can properly pass, could ever compensate Mrs Sharp or other family members and circle of friends for the devastating loss inflicted upon them so suddenly and cruelly" - Judge David Griffith-Jones

Lomas had maintained a clean driving licence for more than 26 years and had no other convictions.

Judge David Griffith-Jones QC said Mohamed “finally saw sense” and pleaded guilty shortly before he was due to stand trial.

“That you failed to see warnings on gantries of trouble ahead is explained that in the period leading up to your collision you were actively engaged in using your mobile phone,” he said.

“There is evidence you made no less than 11 calls and one text message between 5.02am and the moment of your collision at 5.24am.

“Having not seen the messages on the gantry you remained in lane two. You also failed to moderate your speed calculated at between 70-86mph as you approached the scene - a speed that was far too fast in the circumstances.

“No doubt your preoccupation with the use of your mobile phone also explained why, like Mr Lomas and unlike other numerous drivers, you failed to see the obstruction ahead of you until it was too late.

“The combination of features to which I have referred, including in particular your inexcusable use of a mobile phone, drives me to conclude this was careless driving not falling far short of dangerous driving, placing it in the higher category.”

The judge said the range for sentencing was five to nine years.

He added that the tragedy would in all likelihood live with him forever.

Judge Griffith-Jones spoke of the moving victim statement made by the victim’s widow Karen Sharp, giving a graphic description of how her life had been turned upside down.

She did not want her statement read out in court, but quoted one line: “The day Mark died my life stopped.”

“That really said it all,” continued the judge. “Nothing I can do, no sentence I can properly pass, could ever compensate Mrs Sharp or other family members and circle of friends for the devastating loss inflicted upon them so suddenly and cruelly.”

He turned to address Mrs Sharp directly, but she and others had already left court.

“Hearings of this kind are never easy,” he said. “Some members of the family have left, not surprisingly. This hearing will have been a traumatic experience for Mrs Sharp and other members of her family.”