HUNTLEY, P.E.I. — Officials have reported another fish kill in Prince Edward Island, raising to six the number of incidents that have left thousands of fish dead and several rivers damaged.

About 150 dead brook trout were recovered in a 1.5-kilometre section of a pond in Huntley, in the western part of the province.

Officials didn't identify the cause of the kill, but said water, sediment and fish samples had been sent to an Environment Canada lab for analysis.

It's suspected it might have been caused by run-off from pesticides used on farms adjacent to several rivers and streams in the province that have witnessed high fish kills in recent weeks.

Department officials received lab test results back from a kill in the Wilmot River, near Norboro, P.E.I., that showed high concentrations of azinphos-methyl, an insecticide that is lethal to fish.

The Department of Agriculture has restricted the use of the chemical, which can no longer be used in areas bordering water or that could be conduits to water.

"The chemical is in about 10 products that will be added to our restricted-use list," Agriculture Minister Mitch Murphy said Friday, adding that people who want to use it will have to get a permit.

The province is awaiting test results from other rivers that have had fish kills and says it will consider restricting the use of other chemicals if they're found to be in the water systems.

"If we find other products have been the culprits, then we'll take similar action," said Murphy.

Five other river systems have been found to have dead trout and sticklebacks, raising the total number of dead fish to 12,000.

Environmentalists, fishermen and tour operators are urging the government to ban the use of several pesticides, which they say are the sole cause of an increasing number of fish kills.

Across the province, they've watched as fresh rains have brought streams full of dead, glistening fish that float by in water they say is so badly contaminated it kills everything in its wake.

It's thought the pesticides leach into the soil and trickle into nearby water systems, killing marine life before they move out into open ocean.