More than 1,000 fish have been killed in a pollution scare in Northern Ireland, authorities have warned.
Trout, sticklebacks and roach are among the dead species discovered in a stretch of the Oona River near Dungannon in Co Tyrone.
Investigators have blamed an “agricultural source” for the fish kill which is being classed as of “high severity”.
The Northern Ireland Environment Agency (NIEA) and the Inland Fisheries agencies are both investigating the water pollution.
Northern Ireland’s Environment Minister Mark H Durkan has voiced his worries.
“I am concerned about this and I am keeping a close eye on the situation along with NIEA officials,” he said.
Samples have been taken from the river for analysis.
An NIEA spokeswoman said: “Investigations are ongoing and the (fish kill) count is continuing.”
The River Oona runs through south Tyrone and is part of the Blackwater river system.
“The water quality impact of this water pollution incident is being classified as high severity,” said the NIEA spokeswoman.
“Investigating officers have identified a potential source of the discharge and statutory samples have been taken by NIEA.”
The NIEA said the pollution was discovered by a member of the public on Sunday.
The maximum penalty if convicted in a court for water pollution is three months in prison or a £20,000 fine.
A spokeswoman for the Public Health Agency said: “The information that we have is that there is no immediate concern for public health.”