Police Association vice-president Steve Watt says deportees are increasing tension at such events.
A major search operation is underway on the water and in the air.
"It's good to see how other people tackle similar problems."
"We're a tightknit bunch and this is a matter that will make people very affected."
In one example, a woman was stabbed to death by a partner who overheard her making a 111 call.
Asbestos is a workplace killer, WorkSafe said, with about 220 people dying from it each year.
Someone drilling into a gas pipe is believed to be the cause.
The road has been closed at the site of the accident.
Internal Affairs Minister Jan Tinetti has been brought in to bring both sides together to help find a way forward.
