Three people have been found dead inside a water tank on a rural NSW property in what could be a gas poisoning incident.
Police were called to the Gunning property, around 60km north of Canberra, just after 6.20pm, after a man collapsed while working in an empty in-ground cement water tank.
It is understood a second man and a woman went to help the man but also collapsed.
All three were found dead inside the water tank by a neighbour a short time later, who contacted emergency services.
The victims were all believed to be in their 60s and police have established a crime scene.
The deaths are not being treated as suspicious but the Canberra Times is reporting investigators are looking at whether gas from a petrol engine near the water tank may have contributed to the deaths.
A gas detector has been reported as detecting high levels of CO2 just after 8pm.