Ruapehu mayor Don Cameron says police will help to monitor the amount of travellers coming into the district to self-isolate during the Covid-19 lockdown.
"It cannot continue. Stay home," he said.
It follows three confirmed cases of Covid-19 in Ruapehu which are the first for the Whanganui region.
Cameron said the cases reinforced that people needed to stick to the health guidelines.
"It's really important that people only leave their homes to access essential services or to get some exercise but only if it is absolutely necessary," he said.
He said police would be monitoring people and asking questions of anyone who is out and about during this Level 4 alert period to check on what they are doing.
Cameron said the are being closely monitored.
"Public Health are in daily contact with the affected persons, and contact tracing of those they may have come into contact with is well under way. The affected persons are contained and under strict isolation protocols.
The Emergency Operations Centre handling the Covid-19 response for the Whanganui District Health Board has expanded to include Whanganui Civil Defence which will work in partnership with the health-led EOC.
All three of the confirmed Ruapehu cases were New Zealanders who flew back into the country last week and went into self -isolation.
They are males in their 20s who arrived on a flight from Chicago last Monday.
Whanganui District Health Board confirmed the cases on Saturday and said all three had been fully compliant with quarantine requirements and did not need to be in hospital.
Chief executive Russell Simpson said the WDHB, iwi, the health sector and the wider community had plans in place for dealing with confirmed cases.
"We have trained people and systems in place to manage cases, prevent spread and protect the health of our region."
Public Health staff have been in daily contact with the three men, who are all in one house.
Staff are providing daily welfare checks on the three. They are also receiving drop-offs of food and essential supplies.
"I want to reiterate to the community how vitally important it is that people stay home, within their own bubble, so we can contain Covid-19," Simpson said.
"We also remind people to phone, or use the internet, to contact loved ones, especially those who are vulnerable in our community."
The EOC is co-ordinating the response in the WDHB region.
In Waimarino there will be a reduced maternity service from today as there is only one midwife available.
This means all women due to give birth in the next four weeks will be advised to do so in Whanganui Hospital.
Following the confirmation of two new cases of Covid-19 in South Taranaki on Friday, a further four people with confirmed Covid-19 have been identified in Taranaki since Friday, including the first person to be hospitalised at Taranaki Base Hospital with the virus.
Taranaki now has a total of 11 confirmed cases.
Taranaki District Health Board's chief medical adviser, Greg Simmons, is appealing to people to stay in their bubble.
"It's crucial that everyone stays in their bubble. Remain at home. This breaks the chain of infection and stops the virus spreading." • Covid19.govt.nz: The Government's official Covid-19 advisory website