Three people found dead in water tank in Australia Published duration 17 February 2017

image copyright 9news.com.au image caption The three victims were found on a property in New South Wales

Three people have died in a water tank in Australia in a suspected case of carbon monoxide poisoning, police say.

The two men and a woman, all in their 60s, were members of the same family.

Police said one of the men collapsed while cleaning the empty concrete tank, prompting his wife and brother to go to his aid before they also collapsed.

Authorities would investigate whether dangerous petrol fumes contributed to the deaths, said New South Wales Police Supt Andrew Koutsoufis.

"There were high levels of poisonous gas in the water tank by the time police got there," he said.

"A petrol [water] pump being used the clean the tank ... may have been the cause of the build-up of fumes at the bottom of the tank."

Police were called to the property at Oolong, 235km (145 miles) from Sydney, soon after 18:00 (07:00 GMT) on Thursday.

Supt Koutsoufis said a neighbour heard the woman's cries for help and alerted authorities.

"It's an absolute tragic set of circumstances," he said. "The town is hurting at the moment."

The deaths are not being treated as suspicious. Police said a post-mortem would be conducted.