ALLEN PARK, Mich. (Michigan News Source) – A 36-year-old U.S. Postal Service employee died after becoming stuck inside a mail handling machine at a distribution center in Allen Park.

Officials said Nicholas Acker, a maintenance worker, was stuck in a mail handling machine at the USPS Detroit Network Distribution Center (NDC) for six to eight hours before being found dead on Saturday. Firefighters arrived to investigate after his fiance’, Stephanie Jaszcz, reported he did not return home after his shift. She spoke to WDIV.

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“We want to know what happened and how long he was there,” Jaszcz said. “We want to know how he even ended up there and why doesn’t anybody know where he was at?”

Mail handling machines are used to sort and weigh mail and vary in size. Police describe Acker’s death as “accidental” and the investigation is ongoing. The USPS released a statement, saying it is “deeply saddened” by Acker’s death and “thoughts and prayers are with his family.”

The NDC is fully operational currently.