Tens of millions of litres of toxic water has escaped a gold mine tailings dam in the Solomon Islands.
The mine was sold last year by an Australian company back to local landowners for $100.
8,000 people live downstream from the shutdown Gold Ridge mine.
Now, scientists fear an environmental disaster is looming.
The toxic tailings dam of the Solomon Islands Gold Ridge mine is spilling uncontrollably and has been for more than a week after heavy rains.
Tens of millions of litres of water have escaped from the dam containing arsenic and cyanide and other heavy metals.
Downstream live 8,000 villagers including community leader John Keara.
"We are panicking, honestly we are panicking, we don't know what is happening. Woman, pikinini, everyone of us (is) upset."
Flash flooding two years ago shut down the mine and left the tailings dam critically full.
The recent rains have have pushed the spillway to overflow for the first time in more than 20 years.
It's the last resort safety system that protects dams from collapse says Dr Gavin Mudd, an environmental engineer from Monash University.
"Which is the way a dam is designed and it's supposed to be the way it works but the issue though is it's not the end scenario you want, untreated tailings water getting out into the environment."
Last year Australian company St Barbara sold the mine, and all legal liability, to local landowners for $100, after a dispute with the government over emptying the dangerously full tailings dam.
St Barbara in a statement said it has "completed its commitments relating to the sale ... and has no remaining obligations".
As a condition of the sale, St Barbara last November installed a new water treatment plant and pumps to dewater the dam but they were only turned on last month.
Walton Neazon is the chairman of Gold Ridge Community Limited, the company that bought the mine.
"(So far) we've discharged over 200,000 cubic litres of water and the water has almost stopped discharging from the spillway. We have discharged about 96,000 cubic litres of untreated and more than 120,000 cubic litres of treated water."
The uncontrolled flow over the spillway is estimated at another 100,000 cubic litres of water.
After the sale last year, the Solomon Islands government declared the Gold Ridge mine a "disaster zone".
"You can certainly point fingers at everyone in some capacity. At the end of the day the environmental risks have not been taken seriously by all parties involved. That's government, the mining companies and the communities have underestimated it as well."
Water samples are due to be tested at University of Queensland labs in the coming weeks to see just how toxic the tailings dam is, but that won't stop the to spill.
"For Gold Ridge we know there is certainly an arsenic issue in the water with processing ore, it comes from the gold ore. Other heavy metals can include things selenium, mercury is often a very important one, mercury is critically important for public health and the environment. There could be a whole range of others heavy metals like copper and zinc as well. We need to make sure we are monitoring all of those to know what the risks are for downstream and the environment."
An unreleased Health Ministry press release obtained by SBS warns the water "may contain high levels of arsenic".
"Do not use river water for drinking, washing, bathing/swimming or fishing," it says.
The downstream community leader John Keara says they have not heard from the government.
"The government didn't do anything for us. They ignore it, they ignore us. Now we become victim already."
SBS has not received an official statement from the Solomons government.
Walton Neazon says the company has contacted downstream communities.
"We asked them not to use the water, even though the water is clear. That is our concern and we always talk to them about that. The people are still using the water to swim, they are still using the water but we advise them to reduce the usage."
