A motorist driving in the opposite direction told the Herald she saw a car on its roof.
The New Zealand Transport Agency posted on its website that motorists should expect significant delays following the crash. They later posted the crash was now clear and congestion had eased.
SH1 RANDWICK PARK, SOUTHBOUND - CRASH - 7:20AM
Due to a crash south of the Hill Road off-ramp, there is heavy southbound congestion. Please expect significant delays or avoid the area if possible. ^EW pic.twitter.com/fR8piM9XaU
— Waka Kotahi NZTA Auckland & Northland (@WakaKotahiAkNth) March 16, 2018