The son of a Greek millionaire supermarket chain owner has died in a horror crash when he lost control of his Porsche, killing a friend as well as a mother and her toddler.

George Vakakis was driving the rented sports car, with friend Andreas Georgakopoulos in the passenger seat, when they crashed at high-speed into a parked car with a mum and her three-year-old son inside.

CCTV footage captured the moment a fireball erupted killing all four, next to a motorway between the Greek capital city of Athens and the town of Delphi.

It shows the Porsche, driven by the 24-year-old, careering off the motorway at high speed before crashing into the Honda Civic sideways, so hard that both vehicles shoot into a building and explode.

The Honda had been parked at the service station while the driver, a 41-year-old man, got out to use the toilet.

His wife and son were waiting in the parked car.

The moment of the crash
The Porsche driver has lost control

The footage shows the distraught dad and husband come running out screaming. He managed to call the emergency services and tried in vain to help his family.

"It’s horrific. The family was waiting in the parking. They weren’t even on the emergency lane,” a driver passing through told the local news agency, LamiaReport.

George Vakakis
George Vakakis

Mr Georgakopoulos was not wearing a seatbelt and was thrown out of the vehicle's window in the crash but died from his injuries.

Mr Vakakis was the son of Greek millionaire Apostolos Vakakis, the owner of the Jumbo supermarket chain.

He had been visiting family in Greece during a short break from his studies in the United States.

The explosion caused by the crash
The explosion caused by the crash

Police have launched an investigation and said that the Porsche appeared to have been travelling significantly faster than the 120kph (75mph) speed limit.

Mr Vakakis Jr had always been considered the future main heir of his father’s empire which includes more than 80 shops around the world, 52 of them in Greece.

The explosion caused by the crash
Four people, including a child, died in the crash

In 2015, Jumbo’s annual profits amounted to €782million (£666million).

Nobody from the Vakakis family has so far commented on the accident.