At least 12 residents of a large senior care community in New Hope have died of the novel coronavirus, representing one of the state's deadliest outbreaks of the respiratory illness at a single site during the pandemic.

St. Therese of New Hope, which includes a 258-bed nursing home with a troubled regulatory record, said it is working closely with the state Department of Health on a response to the outbreak. The campus also includes independent and assisted-living residences.

The residents who died were between 82 and 96 years old, according to death records reviewed by the Star Tribune.

The first two deaths happened April 6. Most residents died from pneumonia and other respiratory complications caused by COVID-19, the disease that has killed more than 45,000 people nationwide.

Nursing homes across the nation have been under lockdown for weeks to protect their frail and elderly residents, but a wave of deadly outbreaks has raised concerns about whether the preventive measures go far enough. Of the 179 known deaths from the coronavirus in Minnesota, 129 are linked to long-term care facilities such as St. Therese, state health officials said.

The nonprofit organization that runs the senior facility has begun to quarantine all infected residents on a single unit and has instructed staff to treat all residents known to be exposed to the virus as if they could be infected. Employees are being screened for signs of the illness before each shift, the facility said in a statement.

In a statement, St. Therese said it initiated "aggressive infection control measures and proactive screening" March 13 to limit the spread of COVID-19.

These steps include closing its building to all visitors, restricting congregate gatherings and increased sanitation of common areas. Staff are instructed to wear masks and personal protective equipment "during close interaction," according to the statement.

A spokeswoman for St. Therese declined to disclose the number of residents and staff at the facility who have tested positive for COVID-19. St. Therese created a "COVID-19 information line," consisting of a brief recorded message about prevention measures. The recording had not been updated since April 12.

Several families with relatives at St. Therese said they have been repeatedly denied information about the scale of the outbreak, which has made it difficult for them to make decisions about care.

Jessica Christensen, a volunteer caregiver in Brooklyn Park, said she learned this weekend that a 92-year-old woman she cared for at St. Therese had tested positive for COVID-19. Less than 24 hours later, she died of the illness. Christensen said she repeatedly asked staff how many people were infected and was referred to the facility's hotline, which lacked case information. Had she known that multiple people had been infected and died, Christensen said, she might have moved her friend to an alternative facility before she became infected.

"People have been robbed of the opportunity to prepare," Christensen said. "By knowing how widespread [the outbreak] is, they could have gotten their loved ones out before the storm hit. They deserved to know what's coming."

Like many nursing homes, St. Therese has many of its residents doubled up in rooms with beds separated by curtains, which may have contributed to the virus' rapid spread.

Roxanne Diaz said she became frightened that her 80-year-old mother was "in grave danger" based on a troubling phone conversation in early April. During the call, her mother said that her roommate had tested positive for COVID-19, and was repeatedly wandering over to her side of the room because she had dementia and was unaware of the risks of spreading the infection.

Diaz said her mother is bedridden and unable to move around on her own, which made it impossible for her to protect herself from the infected roommate. Her mother also complained that no one had given her a mask, Diaz said.

Days later, Diaz's mother developed a dry cough, fever and vomiting; she would eventually test positive for COVID-19. She is now in stable condition, though Diaz said she remains upset that no one at the facility informed her that people were dying from the virus.

"There was no attempt to shield my mother," Diaz said. "And they were not prepared to deal with patients who are unable, for whatever reason, to practice social distancing."

Founded in 1968 and affiliated with the Catholic Church, St. Therese has a record of health and safety problems. In a 2018 inspection, the facility was cited 11 times for a variety of violations of minimum health and quality-of-life standards.

These included failing to properly empty and remove urinary drainage bags, creating a foul odor in residents' rooms; failure to investigate bruising and alleviate pressure sores; and failure to provide basic grooming and routine dental care for residents.

Each violation caused "minimal harm or potential for actual harm," federal records show.

The nursing home was also fined $19,500 in 2018 after a resident suffered a second-degree burn because the resident's bed was placed next to a heater. Inspectors found that four residents in the facility's memory care unit were put in "immediate jeopardy" of harm after their beds were placed next to heaters. The nursing home responded by removing beds from baseboard heaters and training staff on the safe bed positioning, records show.

In 2016, St. Therese became the focus of community concern after state health regulators uncovered brutal abuse of two elderly residents, based largely on hidden-camera footage.

State Department of Health investigators found that an 85-year-old patient with a severe cognitive disability was repeatedly punched in the face and stomach, causing visible cuts and bruises, while another patient had a bath towel thrown in her face, among other abuses. Other employees at St. Therese of New Hope were caught on video talking on their personal cellphones rather than providing necessary care. The incidents led to criminal charges against two St. Therese employees and the firing of at least eight other staff.