

The Transportation Safety Board of Canada says it's investigating a runaway train incident at a switching yard north of Toronto.

A spokesman for CN Rail says there were no injuries when a string of cars separated from a switching locomotive at the CN MacMillan Yard in Vaughan, Ont.

Mark Hallman says the incident occurred on Wednesday when 91 cars collided at low speed with other freight cars in the yard.

Hallman says no freight cars left the yard, which has mechanical devices to prevent any rail cars exiting the terminal.

Nine freight cars derailed in the incident, and two freight cars on an adjacent track were damaged.

Hallman says there was no release of dangerous goods.