A 22-year veteran of the North Haven Fire Department has died from injuries he sustained while working at an early morning blaze at a four-family home on Monday, the fire chief confirmed, calling the death a tragic loss for his department.

The incident occurred while firefighters were battling the blaze.

A mayday call for a "firefighter down" was issued during the attack on the fire, according to a report released by the department. Firefighter Matthias Wirtz, 46, was located outside the burning building, operating a fire truck. Medical care was provided before he was taken to Yale New Haven Hospital with life-threatening injuries, according to the report. He was later pronounced dead at the hospital.

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The Connecticut State Police fire unit is investigating the cause of the blaze, which displaced 13 residents on Christmas night.

"We worked hard to save him, real hard. We made every effort possible," Fire Chief Paul Januszewski said of Wirtz, noting there was an ambulance and paramedics on the scene because of the fire. He did not elaborate on Wirtz's injuries.

Connecticut firefighter killed

Matthias Wirtz, 46, a member of the North Haven Fire Department and 9/11 first responder, was killed after responding to a call early Monday morning.

Januszewski said he began working for the department around the same time as Wirtz. He said the firefighter was excited about recently being tasked as a driver.

"He was everybody’s friend. He was a great person. He was a great family man," Januszewski said. "He would do anything for anybody."

The fire chief said neighboring fire departments that helped to battle the fire would continue to help his department on Monday as members grapple with Wirtz's death.

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"Through the course of the day today, those departments will continue to support our department in responding to incidents and to allow our members some time to grieve," he said. Fire departments from around the state expressed condolences on social media to North Haven firefighters and Wirtz's family.

Firefighters were called to the multi-family home shortly after 1 a.m. and discovered heavy smoke coming out of the back of the three-floor building. The fire had also reached into the attic.

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Wirtz started his career as a volunteer firefighter in 1996, serving the North East Volunteer Fire Co. #4 in North Haven. He received numerous letters of commendation over the years and was among the Connecticut firefighters who responded to the terrorist attacks in New York City on Sept. 11, 2001.