State Highway 2, just north of Wairoa, was blocked for three hours yesterday morning after stock truck and trailer carrying cattle overturned blocking both lanes.
Police were called just before 10am by a motorist who came across the crash about 2 kilometres north of the Waitua Rd turn-off.
The two men in the truck were trapped and had to be freed by firefighters who were also called to the scene.
They eventually got out the badly damaged cab.
The passenger is believed to have broken his arm and was flown to Hawke's Bay Hospital.
As emergency crews worked at the scene road, diversions were put in place at Wairoa and the Waipaoa roundabout in Gisborne.
Police came across several dead and injured cattle across the road and stock control officers were called in.
Two bulls were killed in the crash, and another had to be put down due to its injuries.
A heavy crane and transporter was used to get the truck and trailer off the road, which was re-opened to light traffic just before 11am.
Officers from the Commercial Vehicle Investigation Unit were looking into the crash. No other vehicles were involved.
Another crash on SH2 north of Wairoa on Sunday injured four young Nuhaka men when about 6.20am.
Three males, aged 16 to 22 years, received life-threatening injuries. All four are said to be in a stable condition in hospital.