The U.S. Attorney's Office for the District of Massachusetts and the Department of Justice's Civil Rights Division announced the joint investigation on Friday.
Of the 25 veteran residents who've died since late March, 18 tested positive for the coronavirus, while three have pending test results, three tested negative and one was unknown, according to the latest information from the state's Office of Health and Human Services on Monday.
At least 59 veteran residents have tested positive, while 31 employees have tested positive, according to the agency. There were 159 veteran residents and 179 employees who tested negative, the agency said.
A spokesperson for the agency released a statement following news of the investigation, saying it's "imperative" that the facility provide a safe environment for residents and staff. The statement also included efforts made by officials during the crisis, including putting Superintendent Bennett Walsh on paid administrative leave and instituting an onsite clinical command team.
Those team members "have assertively responded to the emergency situation and are continually making necessary changes on the ground to protect resident safety," the spokesperson said. "The circumstances that led to the heartbreaking situation at Holyoke Soldiers' Home are the subject of a full and impartial investigation ordered by the Governor, led by Attorney Mark Pearlstein."
Employees have told ABC News that management at the home, including Walsh, did not provide staff with personal protective equipment and that veterans who had been exposed to the virus were placed in overcrowded rooms with veterans who had not been exposed.
Walsh has not responded to requests for comment from ABC News, but did provide a statement to MassLive defending his actions.
The investigation by the U.S. Attorney's Office and DOJ is separate from the independent investigation that Massachusetts Gov. Charlie Baker has ordered.
"It would be difficult to overstate our obligation to the health and well-being of elderly and disabled military veterans and, by extension, to their families. … My condolences to the families of those veterans who died while in the Home’s care; we will get to the bottom of what happened here," U.S. Attorney Andrew Lelling said in a statement.
Cory Bombredi, an organizer with the Local 888 union that represents some of the employees, applauded the new investigation.
"I find the news promising that we now have several sets of eyes looking into the events that led to the unnecessary death of our veterans, and the spread of COVID-19 throughout our membership," Bombredi told ABC News.