Court shown harrowing cellphone footage of Hamilton crash

Cellphone footage of the lead-up to a high-speed crash that left four people dead has been shown at a manslaughter trial in Hamilton.

Police say it shows one of two alleged racing cars reaching a speed in excess of 150km/h.

A car was left split in two when it collided with a van on State Highway 3 near Hamilton Airport on June 24, 2016.

Dylan Cossey, 20, is alleged to have been racing the vehicle at the time.  

In a police interview shown to the court, filmed four days after the 2016 crash, he told a detective he should have stopped.

"I panicked, I didn't know what to do," he is seen telling police. 

"I started slowing down a little bit, then my bro was telling me to 'get, get, get'. I've never seen anything like that in my life. The car was in half, we just knew."

Cossey allegedly fled from the scene with his friend Stephen Jones in the passenger seat. They're both facing four counts of manslaughter.

The court was shown cellphone footage recorded by Mr Jones in the seconds leading up to the crash.

The video shows the Nissan Skyline overtaking the Honda driven by Cossey at around 150 km an hour.

A witness in the Honda can be heard screaming in horror before the screen goes black.

Police say the 13 seconds of footage they have was not the full video but an edited version, the rest of which was deleted. 

Blood tests showed the driver of the Nissan, Lance Robinson, was two and a half times over the legal alcohol limit when he crashed and was killed.  

Methamphetamine and THC were also detected in his system.

In the police interview, Cossey denied he was racing, and said he only reached speeds of 100km/h to 120km/h.

When asked why he didn't call an ambulance by police, Cossey said he was scared.

"I didn't want people to think it was my fault… and I didn't want to be at the scene when the families were coming on."

The trial continues.