Another federal prison in Alberta has been locked down as a precaution after some inmates showed flu symptoms.

Correctional Services Canada says two medium security unit inmates at Drumheller Institution were tested Thursday for COVID-19.

An official says the two inmates have been isolated from others as they wait for the test results.

The medium security part of the prison northeast of Calgary can house up to 582 inmates.

Meanwhile, CSC says COVID-19 tests done earlier this month on a group of less then 10 inmates at Bowden Institution in central Alberta came back negative.

An official says one unit of the prison near Innisfail remains locked down, but other parts are operating under a modified routine.