The Texas Parks and Wildlife Department is investigating reports of dead fish at Rio Hondo's boat ramp, Channel 5 News has learned.

On Wednesday, the department confirmed the investigation to Channel 5 News and said the Texas Parks and Wildlife Department Kills and Spills team were at the site on Monday.

“It is believed to have been a low dissolved oxygen event that happened up stream of the park in the Arroyo Colorado over the weekend,” the department said. “Dissolved oxygen readings taken at the site during the investigation were normal."

The department said the incident is unrelated to the Aug. 9 fire at the Valley Co-Op Oil Mill in Harlingen. The aftermath of that fire led to runoff water polluting the nearby drainage system, killing the fish there.

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