A witness who was present as an American woman died using a suicide pod has spoken out about what happened.

The 64-year-old American woman reportedly passed away “almost immediately” on Monday inside a Sarco pod situated in a remote forest hut near Merishausen, northern Switzerland.

The Sarco pod has been used for the first time. Credit: thelastresort.ch

The Sarco pod provides a new, autonomous method of assisted suicide, and its use has sparked renewed debate over the ethics of end-of-life choices, per BBC News.

The pod, which induces death by oxygen deprivation through nitrogen gas, aims to offer a painless and self-administered way for individuals to end their lives.

The pods were designed by Dr. Philip Nitschke, who is often referred to as “Dr. Death.”

Dr. Nitschke expressed satisfaction that the Sarco performed as intended.

Per de Volkskrant, he said, “I’m pleased that the Sarco had performed exactly as it had been designed to do: that is to provide an elective, non-drug, peaceful death at the time of the person’s choosing.”

He added: “When she entered the Sarco, she almost immediately pressed the button. She didn’t say anything. She really wanted to die.”

Nitschke estimated that the woman lost consciousness within two minutes and was dead within five.

“We saw jerky, small twitches of the muscles in her arms, but she was probably already unconscious by then. It looked exactly how we expected it to look,” he added.

The Sarco pod was created by Dr. Philip Nitschke. Credit: David Mariuz/Getty Images

Dr. Florian Willet, co-president of The Last Resort Association, who co-developed the pods, was the sole witness to the woman’s death.

The woman’s identity has not been disclosed.

Describing the experience, Dr. Willet said her death was “peaceful, fast, and dignified,” per CBS News.

According to The Last Resort website, the death took place outdoors, “under a canopy of trees, at a private forest retreat” in the Swiss county of Schaffhausen, near the German border.

However, the death has triggered a criminal investigation.

Swiss authorities detained several people following the incident, and prosecutors have opened a case on suspicion of incitement and accessory to suicide.

Switzerland has permitted assisted suicide since 1942, provided the individual seeking death is not influenced by selfish motives.

However, euthanasia – where another person directly causes the death of the individual – is illegal in the country.

The American woman, whose identity has not been publicly released, left a four-minute audio message for The Last Resort, an organization supporting her decision.

In the recording, she explained that she had been immunocompromised and in severe pain for at least two years.

She also revealed that her two sons, though not present at the time, supported her decision “100 percent.”