Gov. Janet Mills is among voices calling for Central Maine Medical Center nurses to be reinstated after they were fired just before a vote to unionize.

Last week, CMMC said 15 nurses had been fired, and five others are suspended for reasons they claim are unrelated to efforts to unionize.

In a letter, Mills said the firings heighten concerns that the hospital’s new owners, the California-based nonprofit Prime Healthcare Foundation, are failing to meet obligations outlined in their agreement with the state to acquire the hospital.

In her letter to hospital’s president and CEO, Mills said:

“I strongly urge you to immediately reinstate every nurse who has been wrongfully fired or suspended. Failure to do so will make clear to Maine people that Prime Healthcare is prioritizing corporate interests over the commitments it made to the State of Maine to deliver the quality health care which Maine people expect and deserve.”

Maine Democratic Congresswoman Chellie Pingree also sent a letter to Prime Healthcare CEO Dr. Prem Reddy, calling for an end to “alleged intimidation and retaliation against nurses.”

Maine Congressman Jared Golden was among congressional Democrats who co-signed the letter.

The hospital says the nurses were suspended or fired for ongoing violations of hospital policies that put patients at risk.

The vote to unionize is set to take place on Thursday.