Federal public servants are being threatened with legal action if they don’t repay money they were overpaid during the error-plagued rollout of the Phoenix pay system nearly a decade ago, Radio-Canada has learned.

The government has authorized private debt collection companies to pursue repayment from those recipients, some of whom left government years ago and were never informed of the overpayments, according to Canada’s largest federal public sector union.

In some instances, tax refunds, tax credits and federal benefits are being withheld and interest is being added to balances, according the Public Service Alliance of Canada (PSAC), which is calling on the government to stop pursuing overpayments that fall outside a six-year limitation period.