The railroad responsible for the deadly crash in Lac Megantic, Que., received numerous warnings from Transport Canada about securing its rail cars, the CBC reports.

Montreal, Maine and Atlantic Railway (MM&A) was never sanctioned by Transport Canada for violating the rules, but a CBC investigation shows the MM&A was notified at least eight times between 2004 and 2012.

In July, a MM&A train filled with mislabelled crude oil rolled down a hill, derailed and exploded in the middle of Lac Megantic, killing 47 people.

The deadliest train crash in Canadian history is still under investigation.

The Transportation Safety Board has previously said the train had been left unattended and not properly secured.

The CBC found that some of the violations involved a station in Nantes, Que., which is where the train that rolled into Lac Megantic had been parked.

The violations fall under Section 112 of the Canadian Rail Operating Rules, CBC reported.

"When equipment is left at any point a sufficient number of hand brakes must be applied to prevent it from moving," the section states.

A few days after the fatal crash, the MM&A was given another violation, CBC reported, for not securing a train at a location five kilometres from Lac Megantic. A train with comprised of five locomotives and 98 cars was left unattended, without enough handbrakes to keep the train from moving, CBC found.

MM&A now faces at least $50 million in wrongful death lawsuits and has filed for bankruptcy.

No one from Transport Canada or MM&A were immediately available for comment.