The Malta Ship Registry is conducting an investigation into the Zim containership incident in which several boxes caught fire and more than 100 others fell overboard during a storm off Canada.

A fire erupted on 22 October in containers carrying hazardous chemical potassium amyl xanthate aboard the 4,253-teu Zim Kingston (built 2008) while the vessel was anchored 4.7 nautical miles off the Port of Vancouver.

"A preliminary assessment into this occurrence has been opened to determine the extent and scope of the safety investigation," Kevin Ghirxi, an investigator for Malta, told TradeWinds.

Ghirxi, the Marine Safety Investigation Unit's head of marine safety investigations, added: "The preliminary assessment is not only considering the fire but also the loss of containers overboard, which happened during rough weather."

At least another 109 boxes fell into the sea, including two containing the toxic substance, according to the Canadian Coast Guard (CCG).

The CCG, which is also investigating the incident, identified four boxes from the Danaos Corp-owned ship that washed onto the shores of Vancouver Island in Cape Scott.

Danaos, which is responsible for the incident as owner of the vessel under Canadian law, has hired contractors to begin removing refrigerators and four containers carrying them from the shores of Vancouver Island.

The CCG, which is still looking for more containers, on Friday confirmed that the fire aboard the Zim Kingston was fully extinguished.

Transport Canada will direct the ship, which is carrying about 2,000 container, to a nearby port for unloading once damaged boxes on the vessel are secured or removed and necessary repairs are done.