HALIFAX -- Poets and politicians remembered those who died and those who struggled to rebuild a shattered city as a sombre ceremony was held Wednesday to mark 100 years since the Halifax Explosion.

The wartime blast resulted from a collision of two ships in the harbour and led to approximately 2,000 deaths and an estimated 9,000 wounded.

A large crowd turned out in cold rain at the Fort Needham memorial site, not far from where the French ship SS Mont-Blanc erupted and wiped out the city's north end and a Mi'kmaq village across the harbour.

A bell was rung at the precise minute of the explosion's anniversary, while a cannon was fired from Citadel Hill and many city residents fell silent for a minute.

George Elliott Clarke, the Nova Scotia-born parliamentary poet laureate, recited a poem recalling the poignant moments leading up to the 9:04 a.m. detonation, including the imagined last goodbyes of children as they went off to school in the city's Richmond neighbourhood.

"Punctual salutations resonate in Richmond homes as spouses trudge to factory or menial jobs. Children troop to school and many of those cheery, kissed-cheek goodbyes will prove unknowingly final," he said, reading from the soaked paper of his poem.

Then, the poet imagined the multi-coloured smoke cloud hovering over the harbour on Dec. 6, 1917.

"Lavender plumes disgorged from wrathful, aerated char ... the skies tinged, absinthed, chartreused here, gangrened there, or rose pink and chocolate there, as if one spying spumoni ice cream spirited into fumes," he said, reading from the soaked paper of his poem.

Clarke also remembered Vince Coleman, the railway dispatcher who "alert and alarmed, tapped out urgent, percussive Morse (code)" to warn an incoming train before he died in the explosion.

His grandson, Calgary lawyer Jim Coleman, also spoke at the ceremony, recalling how many families had in earlier generations turned away from memories too difficult to recall.

He said after 100 years that is changing, and reminded the audience how valuable it is to remember stories like his grandfather's.

"He had a choice. He had a choice to stay or a choice to leave and try to save his life. We believe he made the right choice. He stayed and for that many people lived," he said.

Mayor Mike Savage asked spectators to remember those "who lived 100 years ago, those who were killed, those who survived and those who rebuilt."

The catastrophe remains the worst human-made disaster in Canadian history and was the largest artificial blast prior to the nuclear bombing of Hiroshima.