SMITHTOWN, N.Y. (CBSNewYork) — Police are investigating the death of a worker at a sewage treatment facility in a Smithtown apartment complex.

Police said 43-year-old Richard Dennison, an employee at United Cesspool Service, fell into a vat at a sewer treatment plant at Avalon Commons around 6:45 p.m. Tuesday.

Dennison, of Central Islip, was pulled out of the vat by emergency responders and was pronounced dead at the scene.

The cause of death has not been determined.

No criminality is suspected.

The Occupational Safety and Health Administration will be notified.

The investigation is ongoing.

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