A bush fire which threatened homes near Blenheim this afternoon is being treated as suspicious.
Emergency services scrambled for more than two hours to get the large fire, in the suburb of Wither Hills, under control.
The blaze is now contained and under control, the Marlborough Kaikoura Rural Fire Authority said, and about 60 people who were evacuated from nearby homes have been allowed to return.
Six helicopters and 10 fire appliances were used to battle the blaze on the banks of the Taylor River near West Mount School, off Taylor Pass Rd, principal Marlborough Kaikoura rural fire officer Richard McNamara said.
The cause of the blaze was unclear, McNamara said, but the fire was believed to be "suspicious". A total ban against fires remained in place for the Marlborough region.
Specialist fire investigators are now at the scene investigating how the fire started.
Crews were called to the scene about 4.30pm, southern fire service communication shift manager Tim Reynolds said.
The fire was brought under control about 8pm.
Firefighters will remain at the scene overnight to dampen down hot spots, McNamara said.
"Our crews will now need to work hard to cement the gains from their efforts this afternoon."
Bulldozers will be brought in tomorrow to help control any underground hotspots.
McNamara said as a "precaution" residents close to the fire were asked to evacuate their homes, but have since been allowed to return to their properties.
A strong, south-easterly wind had been blowing the fire towards some homes, police said. Spot fires had also sprung up because of the wind.
One road, two intersections and the entrance to a bike track were cordoned off because of the blaze.
Woodmor Road, Wither and Taylor Pass Road intersection, Forest Park Drive and Taylor Pass Road intersection and the bike track entrance on Taylor Pass Road were all closed to traffic about 5.45pm.
However, the roads have since been reopened to residents but would remain closed other members of the public, McNamara said.
Walkways near the river were also closed and emergency services asked members of the public to stay well away from the area.