Mexican authorities say a mass die-off of fish at a lake in western Mexico was not due to natural causes.
been removed from Lake Cajititlan in Jalisco state.
The cause of the die-off has not been determined but the state environment department said late Sunday it was not due to natural causes.
Workers using shovels, a bulldozer, boats and wheel barrels removed the dead fish, which are being sent for testing.
It was the fourth time this year there has been a die-off at the shallow lake, which sits between Guadalajara and Lake Chapala.
Some had speculated abrupt changes in temperature or oxygen levels may have been responsible for earlier incidents.