The Drumheller Institution is back under a lockdown this week.
The lockdown was put into place in the Medium Security Unit on Thursday morning around 7:50 a.m.
A statement from Correctional Service Canada says it's to allow staff members to conduct an exceptional search.
Visits to the prison have been suspended until the search is completed.
Normal operations will resume once it's considered safe to do so.
Just last week, a guards union spokesman alleged there is a problem with the drug Fentanyl at the Drumheller pen.