The incident occurred at about 6:50 p.m. on Monday, Sept. 2 at Wilson Farm Park near Lee and Wilson roads in the Chesterbrook area of Tredyffrin Township.
Police were called to the scene for reports of a missing child.
When the officers arrived, they searched the immediate area and one of the officers found the boy in a nearby pond unresponsive, Captain Tyler Moyer with Tredyffrin Township police told Daily Voice.
The officers immediately started resuscitation efforts and the child was rushed to the Children's Hospital of Philadelphia's King of Prussia campus. He was pronounced dead a short time later, Moyer said.
It's prohibited to swim or fish in the retention pond, Moyer said, noting it's used for the sprinkler system.
The boy was under the supervision of a nanny, police said.
Police are now trying to figure out how the toddler got into the water.
"On behalf of the Tredyffrin Township Police Department, we are deeply saddened by this tragic event, and we send our deepest condolences to the child’s family," police said in a statement.
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