Police converged on the area and Armed Offenders Squad members were on the way.
A spokeswoman said police were searching for someone, but had no further details.
A witness said a car had been abandoned in the middle of State Highway 94, near the town.
Three police cars were there, and a police dog and handler were searching a nearby field.
A resident of nearby Tutoko Lane said she had received a phone call telling her to stay inside.
A St John spokesman said an ambulance was sent but not needed. Southern Lakes Helicopter chief pilot Sir Richard Hayes, who lives near Te Anau, said a helicopter had picked up members of the Invercargill Armed Offenders Squad from near Winton and was flying them to the scene.
He said police officers and a police dog had come through his section on Tutoko Lane searching for someone, but he did not think anyone had been on the property.
The NZ Transport Agency says SH94 is closed between Sandy Brown and Kakapo Rds.
