A hospital declared her dead. Then mourners heard sounds from her coffin.

Mourners gathered at the wake of a woman in central Ecuador were shocked to find she was still alive and breathing inside her coffin.

Relatives suddenly heard Bella Montoya, a former nurse, knocking on her coffin, according to the Associated Press. A closer inspection showed that the 76-year-old woman was still alive — hours after she had been declared dead.

“After about five hours of the wake, the coffin started to make sounds,” her son, Gilberto Barbera, told the AP. “My mom was wrapped in sheets and hitting the coffin, and when we approached we could see that she was breathing heavily.”

“My mom started to move her left hand, open her eyes, her mouth” and was struggling to breathe, local newspaper El Universo quoted him as saying.

In a statement Sunday, the Ministry of Public Health said authorities were investigating the case.

Montoya was taken to the Martín Icaza Hospital in Babahoyo on Friday after suffering from a suspected stroke, and went into cardiorespiratory arrest. The doctor on duty confirmed her death after resuscitation efforts failed, according to the government statement.

Her son told El Universo that his mother was admitted to the hospital at around 9 a.m. on Friday. “And at midday, a doctor told me that my mom had died.”

Relatives gathered for the wake the same afternoon — and called emergency services when they realized she was still alive. Emergency responders returned her to the same hospital where she had been declared dead just hours earlier, according to local media.

A video from the scene showed several people attending to the woman as she lay in the open casket, still wearing her hospital bracelet, and opening and closing her mouth.

Montoya’s condition remains serious, however. According to the ministry, the patient is in the intensive care unit, where she has been intubated.

There have been other cases of patients waking up after mistakenly being declared dead by medical staff.

In February, a hospice care facility in Iowa was fined $10,000 for falsely declaring the death of a patient with early onset dementia. The woman later woke up in a body bag at a funeral home, but died days later with her family by her side, according to a state report.

She was presumed dead. Then she woke up in a body bag gasping for air.

In another case, a man took a breath just minutes after medics pronounced him dead. Weeks later, he was able to leave the hospital, and subsequently told The Washington Post that, while the incident took a toll on him, he was thankful to be alive.