Seventy-nine workers at the Mayo hospital in Albert Lea, Minn., ended their one-day strike Wednesday over stalled negotiations only to find that Mayo has locked them out for one week.

A spokesman for the Service Employees International Union said its members were met at the doors of the hospital Wednesday morning by Mayo management and security and told they could not return to work until Dec. 26.

The hospital previously said it would hire replacements for the striking workers on a one-week contract. A handful of the striking workers, including the maintenance workers who operate the hospital boiler, were allowed back to work Wednesday.

Mayo followed through with the lockout even though Lt. Gov. Tina Smith urged them to allow the employees to go back to work. Smith also chairs the corporate board overseeing Mayo’s $5.6 billion expansion in Rochester.

The union claimed it was the first health care lockout ever in Minnesota.