A Belgian steamer and a French freighter were both loaded with ammunition. After the collision the resulting explosion leveled a large part of the town of Halifax and many of the towns inhabitants were killed instantly with an estimated 8,000 injured. The 8 million tons of TNT on board the two ships was being sent across the Atlantic to be used in France.

Ships were gathering in Halifax before embarking on the ocean crossing as a convoy. While out at sea there was a constant threat from attack by the German navy. The British navy ship ‘HMS High Flyer’ was assigned to lead and protect the convoy. The French freighter the ‘Mont Blanc’ had arrived from New York with its load of TNT and entered the harbour on a foggy morning. Due to the poor visibility it collided with the Belgian boat ‘Imo’ also laden with a full load of ammunition. Both ships were immediately abandoned by their crews as a fire erupted.

A British ship, the ‘Pictou’ was at a pier also loaded with ammunition. The crew set the boat free from its moorings and fled the scene after seeing the collision. The ‘High Flyer’ was the only ship to take any steps towards stopping the disaster. 23 men were sent towards the fire with the task of attempting to sink the two ships. As they arrived beside the ships a massive explosion occurred, the 23 men on that detail never stood a chance of surviving the explosion.

The resulting explosion sent a shower of burning debris throughout the town of Halifax. A large wave had also been caused by the explosion and ships at the piers were lifted out of the harbour and onto the dockside. A Canadian army officer stationed near the scene described it as follows. ‘All that could be seen for a great circumference were burning buildings, great mounds of iron and brick in the streets and dead bodies.’ An area measuring 2.5 miles all around the harbour was completely destroyed, the explosion when it happened could be felt from miles away. The wave of water that carried the ships out of the water also hit a navy ammunition store located nearby, the wave possibly saved that from adding to the devastating scene.

Many of the buildings in the town were busy, the railway station collapsed after the blast and many were crushed inside. A sugar plant collapsed killing another 100. One of the worst hit buildings was a school, less than 10 survivors from a school that contained 500 students. The death toll was said to be between 1,200 and 4,000. The actual figure will never be known because so much of the town was obliterated on that day with no trace of many of those that perished. A snowstorm that night helped to extinguish the flames, over 25,000 people were made homeless in the wake of this disaster.