A malicious fire broke out at 4.20 pm in a warehouse with 30,000 m² of covered area over two levels that housed archives and a reefer shed including a decommissioned refrigeration unit containing 5 tonnes of ammonia (NH3). The flame front reached 350 m just 15 min following the fire alert. A safety perimeter was established and significant emergency resources deployed including approximately 100 fire-fighters, 2 oceangoing tugs, etc. The evaporator-condenser units exploded in the fire, releasing 2 tonnes of NH3 gas into the atmosphere. A CMIC unit (mobile chemical intervention unit) took samples (4 ppm of NH3 in the fumes onsite, negative upon measurement at 300 m and 1,200 m). The fire was brought under control at the end of the day. The refrigeration unit was emptied in the following days and the NH3 was stored in containers.