Thieves have looted homes in flood-ravaged areas of Mataura and Brydone, Southland.
Two unattended homes have been burgled and "unknown people" have been spotted on and around rural properties in Mataura and Lumsden.
The strangers fled when confronted, Gore Senior Sergeant Cynthia Fairley said.
"We've seen an amazing response from people who've been helping neighbours and fellow residents after the floods, but unfortunately some properties have been targeted by thieves while they've been left unattended."
Thousands of people in Southland towns were evacuated as floodwater swept across Fiordland, Southland and South and West Otago from Monday to Wednesday.
Water inundated low-lying homes, businesses and farms, closed numerous highways and roads and cutting off Gore for more than 24 hours.
Police have stepped up patrols in Mataura, Gore and Wyndham since the evacuations and called in a team from Canterbury to assist, Fairley said.
Investigations into the burglaries were ongoing.
"Police urge people to take steps to prevent easy access to their property, lock and secure their homes and valuables, invest in good security and alarm systems, and engrave tools and valuables."
Police also asked people repairing fences or cleaning up flood damage to stay vigilant and call 111 immediately if they saw unusual activity, people or vehicles.
"This can also be a time of high stress and fatigue for residents, farmers and workers as the full impact of the flooding sinks in," Fairley said.
Trained counsellors could be contacted on 1737, a free, 24/7 text and call service number, she said.
"We want people to remember to eat, rest, and take care of one another, and to reach out to the Rural Support Trust and Federated Farmers if help is needed."
Fairley thanked volunteers from Fire and Emergency NZ, Civil Defence, NZDF and local community boards for their work and support during and after the flood.
Anyone with information on the burglaries, or who had been a victim of crime in the area should call police on 105, or Crimestoppers anonymously on 0800 555 111.
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