ST. PAUL, Minn. (WCCO) — Flags are being flown at half-staff in St. Paul on Tuesday after the sudden death of a firefighter who was on-duty Monday night.

St. Paul Mayor Chris Coleman ordered the flags at all city facilities to be flown at half-staff in honor of paramedic/firefighter Shane Clifton. He was on-duty at Station 17 Monday night when he suddenly died of cardiac arrest.

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According to the St. Paul Fire Department, Clifton told his colleagues at Station No. 14 in Merriam Park that he felt sick around 5 p.m. Shortly after, he collapsed after going into cardiac arrest. Clifton’s fellow firefighters and EMTs came to his aid and took him to Regions Hospital, where he later died.

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Clifton was a Navy veteran who worked as an emergency department technician for Unity Hospital in Fridley and Allina EMS before he came to the St. Paul Fire Department in 2007.

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Clifton was the first firefighter in the department to die while on duty since 2009. He leaves behind two children. He was 38 years old.