ESTERHAZY, Sask. -- Full operations have resumed at the Mosaic potash mine in Esterhazy, Sask., after some tense moments earlier this week.

More than 300 miners were trapped underground for much of the day on Monday when a fire broke out at the K2 facility.

They rushed to refuge stations to wait until the fire had been extinguished and the smoke cleared.

Mosaic's Brad DeLorey says the investigation into what happened has been completed but a final report has not yet been issued.

He says the outcome proves that the company's emergency response plan works and that employees are well-trained to handle such emergencies.

All of the workers who were trapped are scheduled to head back underground for their next shift.

DeLorey says counselling is available for anyone who needs it.

DeLorey says a piece of mobile mining equipment was the cause of the fire, but more details than that are not yet known.