It was a moving tribute Sunday morning in London to firefighters who lost their lives, including those during the Sept. 11 terrorist attack in New York City 15 years ago.

A ceremony was held at the London Fire Department’s Memorial Headquarters on Horton Street with a crowd gathered along the sidewalks under sunny skies.

The ceremony was led by London Professional Firefighters Association President Jason Timlick and included the placement of fire uniforms and helmets at the memorial plaque on site.

Local firefighter Cpt. Vincent Hart was also remembered in the ceremony. Hart lost his life in 2014 to lung cancer, which is considered an occupational disease of firefighters.

The fire department’s chaplain, Fr. John Comiskey, offered a prayer, noting, “It’s my duty…to pray for those going into duty each day.”

As well the ringing of the ceremonial bell was performed and Amazing Grace was played by a lone piper.

The fire department dispatcher sounded on scanners throughout the city in memory of the fallen.

Across the country and in the U.S., ceremonies were held to mark the 15th year anniversary of the attacks that killed nearly 3,000 people, including 24 Canadians.

"On this solemn day, we join with the families and friends of the victims to remember and honour those who fell. We also offer our heartfelt support to those still struggling with the physical and emotional injuries they sustained on 9/11,” said Prime Minister Justin Trudeau.

"We recognize the extraordinary courage and bravery of the first responders on that day and the days that followed. We honour the EMTs, the firefighters, the police officers, and all those who ran toward the sounds of danger and the plumes of smoke, risking their lives so others might live.”

The U.S. marked the day with victims' relatives reading their names and reflecting on a loss that still felt as immediate to them as it was indelible for the nation.

"It doesn't get easier. The grief never goes away. You don't move forward -- it always stays with you," Tom Acquaviva, who lost his son, Paul Acquaviva, said as he joined over 1,000 victims' family members, survivors and dignitaries at ground zero under an overcast sky.

- With filed from The Associated Press