NEW YORK (AP) – For nearly nine months, investigators have tried to find out who put a clear plastic bag of highly explosive chemicals in Central Park that exploded July Fourth weekend.

The homemade concoction blew up when a tourist from Virginia stepped on it. Connor Golden lost his left foot, and doctors amputated his leg below the knee.

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New York City police and federal agents have tracked the origins of the bag, identified the chemicals in it and reviewed thousands of hours of footage. But the case remains unsolved.

Investigators are hoping new images will help them learn who placed the bag by a rock near the park’s southeast entrance.

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The park gets about 250,000 visitors every day.

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