(CNN) An upstate New York correction officer was severely injured Sunday after opening an explosive package sent to his Floyd home, the Oneida County Sheriff's Office said.

The 52-year-old unidentified officer's upper body was severely burned in the explosion, which happened around 8 a.m. Sunday, Oneida County Sheriff Robert Maciol said in a statement on Facebook. He was initially sent to St. Elizabeth Medical Center in Utica for treatment and later transported to SUNY Upstate Medical University Hospital in Syracuse.

A neighbor told CNN affiliate WKTV the explosion sounded like "two cars hitting head-on." The explosion led to a closure on Old Floyd Road for several hours on Sunday while an investigation was underway, during which residents were asked to stay in their homes.

The officer works for the New York State Department of Corrections but it was not immediately clear if the incident is connected to his employment, Maciol said. Oneida County is home to three medium-security New York State prisons that house inmates from across the state.

The Oneida County Sheriff's Office is being assisted by the New York State Police, the Utica Police Department, the NYS Department of Corrections, and several federal agencies.

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