Smoke believed to be from a suspected burnoff led to one of three crashes in Hawke's Bay on Saturday.
Emergency services were called to the two-vehicle collision on State Highway 2, near Ōtāne, about 9.30am on Saturday.
Police said smoke in area from a suspected burnoff was causing "significant visibility issues" along the highway at the time of the crash.
Northbound traffic was diverted onto Higginson St and southbound traffic was diverted up to Te Aute Trust Rd.
Nobody was injured during the crash and the road reopened about 11.15am.
Earlier that morning, a car rolled down a bank on Te Mata Peak Rd in Havelock North.
Emergency services were called to the crash about 4.17am.
Fire and Emergency New Zealand said nobody was inside the vehicle when crews arrived at the scene.
The crash came just two weeks after a car crashed into a fence on Te Mata Peak Rd on May 20.
The driver also left the scene.
Later on Saturday, a person sustained minor injuries after a car crashed into a ditch in Hastings.
Emergency services attended the single-vehicle crash on Te Aute Rd, Pakipaki, about 12.20pm on Saturday.
Police said one person with minor injuries was assessed at the scene after crashing into a ditch, but did not require further treatment.
A FENZ spokesman said nobody was trapped and the driver walked away from the vehicle unassisted.
A tow was arranged for the crashed vehicle, police said.
Meanwhile, police are investigating after a 10-metre stretch of hedge was set on fire in Hastings on Saturday night.
Emergency services were called to the fire on Windsor Ave, in the Hastings suburb of Parkvale, about 11.45pm on Saturday.
Fire and Emergency New Zealand said fire crews arrived to find a 10-metre stretch of hedge on fire.
One fire crew was on scene near the Hastings Top 10 Holiday Park for an hour and a half.
A FENZ spokesman said the fire is being treated as suspicious.
Police said officers attended and looking into the cause of the vegetation fire.
Anyone with information is urged to contact police.