Gardaí and Offaly Fire Services rushed to the Grand Canal in Edenderry on Sunday morning where a car had entered the water in dangerous conditions.
Firefighters entered the water but gardai have said no one was injured in the incident.
They also said: "Driving conditions have been dangerous overnight and early this morning with dense fog and ice."
They urged drivers to take care over the coming days and weeks as temperatures plummet and driving conditons worsen.
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