A class action lawsuit by victims of the Lac-Mégantic explosion will seek damages from the company that extracted the oil and the company that was to refine it as well as the rail company that was shipping it.

Irving Oil Co., one of Canada’s largest companies, and Dakota Plains Holdings, the North Dakota firm that extracted the oil, were added as defendants to a class action lawsuit filed Monday.

On Monday, a group of Lac-Mégantic, Que., citizens filed suit against the owners of the Montreal, Maine and Atlantic Railway, after one of its trains carrying 72 tank-cars of crude oil derailed and exploded July 6, destroying the town's core.  As of Tuesday, 38 bodies had been recovered from the site and at least 12 people were still missing and presumed dead.

Irving Oil was set to refine the oil. The other defendants are Dakota Plains Holdings, which extracts the oil from the Bakken formation in North Dakota, and its parent company World Fuel Services Corp.

The lawsuit alleges that the companies involved failed to ensure the highly flammable contents of the tankers were properly contained and safely transported.

Among the Lac-Mégantic residents represented by the class action are Guy Ouellet, whose partner, Diane Bizier, died in the explosion and Yannick Gagné, the owner of the popular restaurant, Musi-Café, which was destroyed as a result of the derailment and ensuing explosions.

The suit seeks compensation for the damage caused by the tragedy, but no dollar figure has been publicized.