NORTH HAVEN, Conn. (WTNH) — A North Haven firefighter who died in the line of duty Monday died of heart disease, according to Connecticut’s chief medical examiner.

Officials have identified the firefighter as 46-year-old Matthias Wirtz, a 22-year veteran of the North Haven Fire Department. He leaves behind his wife and mother.

On Wednesday, Wirtz was transported from the Medical Examiner’s Office to the North Haven Funeral Home.

News 8 learned Wirtz was also a first responder during the 9/11 terrorist attack in New York City in 2001.

46-year-old Matthias Wirtz, a 22-year veteran of the North Haven Fire Department

The incident began when a 2-alarm blaze erupted in a home on Quinnipiac Avenue just after 1 a.m. Additional crews from surrounding communities were called in for support, and the fire was put out by 4:30 a.m.

North Haven Fire Chief Paul Januszewski said Wirtz was found injured outside of the home during this time, where he had been operating a fire engine. Medical care was immediately initiated, and he was transported to Yale-New Haven Hospital for life-threatening injuries.

Wirtz’s cause of death is listed as hypertensive and atherosclerotic cardiovascular disease, with a contributing condition listed as a bicuspid aortic valve.

Wirtz was later pronounced dead at the hospital. The local firefighters union said he was surrounded by his crew members when he passed.

“He’s the kind of guy that would do anything for anybody at the drop of a hat,” said Lt. Jeffrey Haag, North Haven Fire Department. “All you had to do was ask.”

Haag says Wirtz’s job was to maintain and drive the fire engine, working from the fire station on Quinnipiac Avenue.

To help them through this difficult time, support has been pouring in from near and far for the fire department, the North Haven community, and his family.

“While we’re not able to answer every text or phone call that comes in, we appreciate the support and I want everyone to know that,” said Deputy Chief Scott Bisson.

Watch the video above to learn how fire departments across the state are honoring Matthias Wirtz.

All four units of the building were damaged due to the blaze. The Red Cross is assisting 13 residents who have been displaced as a result.

None of the residents were injured in the fire, officials said.

North Haven fire officials said that the State Police Fire Investigations Unit will take charge of this investigation. Officials are still investigating the scene, and have not identified a cause for the fire yet.

Gov. Ned Lamont has ordered flags to be lowered to half-staff for Wirtz. They will remain lowered until sunset on the day Wirtz is interred.

“The passing of North Haven Firefighter Matthias Wirtz is heartbreaking, and we honor his bravery and courage in responding early this morning to a multi-alarm residential fire, where over a dozen people have become displaced,” Lamont said in the written announcement. “This is particularly upsetting as it comes at a time of year when families and friends are gathering to celebrate the holiday season. His passing is a painful reminder that first responders work every single day of the year, 24 hours a day, and often miss holidays with their families in order to protect the people of our state. My heart is with his family, friends, and colleagues in the North Haven Fire Department.”

The local firefighters union released the following statement on the passing of Wirth:

“The Uniformed Professional Fire Fighters Association of Connecticut and North Haven Fire Fighters Local 2987 regret to announce the passing of Brother Mattias ‘Matt’ Wirtz. Brother Wirtz passed away as the result of injuries sustained while battling a multiple-alarm house fire in the early morning hours of December 26th. Brother Wirtz served the North Haven Fire Department with distinction for the past 22 years.”

The union president Peter M. Brown said funeral arrangements will be announced when they become available.

A procession transporting Wirtz from the hospital to the Office of the Medical Examiner was held on Tuesday.