Details are still scarce as armed police and specialist negotiators remain locked in conversation with a man who's barricaded himself inside a Levin property.
Emergency services were called to the Bledisloe St address on Thursday afternoon and have been camped outside the property ever since.
Nearby residents were evacuated as a precaution, with some spending the night in motels and at the Horowhenua Library and face another night away from home on Friday should the situation not resolve itself.
Police said the man who barricaded himself inside the property was threatening self-harm. Stuff said the man called its Palmerston North-based newsroom on Thursday morning, claiming he was about to be evicted unlawfully.
The man also reportedly said he had chemicals and weapons at the house. Asked about this during a Friday afternoon news briefing, Manawatū area commander Insp Sarah Stewart said police didn't "have any information specific to that, but we are taking this very seriously and that is why we have asked people to leave the area".
Stewart said the cordons in place in the area - on Bledisloe St between Freyberg and Cobham Sts - and making sure people were outside those cordons was to ensure people's safety.
Police also had the man's safety in mind while working to resolve the incident, Stewart said.
"We deal with each new piece of information, each new opportunity as it arises," she told reporters.
The incident was being taken "very seriously", she said.
"We are communicating with the individual involved and are very hopeful we can resolve this safely."
Stewart also confirmed officers were called to an incident on Bledisloe St earlier in the week but could not go into further details.
Any directly affected residents who had concerns were being asked to visit the Levin police station, or call 105 and quote file number P051449147.
