By Team

MIAMI (CBSMiami/AP) – Wildlife and environmental officials are investigating exactly just what killed thousands of koi and other exotic fish in several residential ponds in a South Florida neighborhood last month.

An inspector first responded April 23 to the Coconut Grove area of Miami after fish kills were reported earlier that week to the Miami-Dade County Division of Environmental Resources Management, spokeswoman Tere Florin said.

READ MORE: State Blames Bank After Florida Educators' Bonus Checks Bounce

Staff collected well water samples Wednesday at Simpson Park near downtown Miami, as well as a pond that had experienced a fish kill, officials said.

“We will be sampling for a wide variety of parameters to try to identify any possible connections between the well water and the death of the fish,” Florin said. “However, at this time, we are still unsure of the cause.”

READ MORE: COVID-19 Booster Shots Now Available At Select CVS Pharmacies

Around the time of the fish kills, residents reported some dead blue jays and a dead raccoon in the area, but officials are not sure if they were connected to the fish. It also was not clear if there was any danger to residents.

The case also has been forwarded to the Florida Fish and Wildlife Conservation Commission, which is the lead agency in the investigation. Spokeswoman Susan Neel said they are planning to analyze several frozen fish from a private pond owner.

MORE NEWS: Southwest Ranches Investigation, Police Won't Say What They Are Looking For

(© Copyright 2021 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.) Team