A man looks at the fruit of a Cerbera odollam tree in Trivandrum, India, in 2004. (AFP via Getty Images)

They call it “othalanga” or “the suicide tree.”

The plant, whose scientific name is Cerbera odollam, is as infamous as it is ubiquitous in Kerala, India, where it grows wild along the southwestern coast. The thin-branched, flowering tree bears a deadly harvest: a softball-sized fruit with seeds so toxic they can stop a heart. In the 19th century in Madagascar, where the tree is also found, thousands of people per year died after consuming the seed in “trials by ordeal” believed to determine whether they were guilty of witchcraft or other crimes. And a 2004 study found that it’s responsible for roughly a death per week in Kerala, most of them suicides. Researchers believe that more people have taken their own life using othalanga than any other plant in the world.

On Thursday, another death was added to the suicide tree’s account: a teenage athlete who consumed the fruit as part of an apparent suicide pact with her three roommates, the BBC reported.

The young woman, Aparna Ramabhadran, died at Kerala’s Alappuzha Medical College from heart failure, according to the New York Times. The three others remain at the hospital in critical condition — one has been outfitted with a pacemaker to counter the poison’s heart-stopping effects.

The young women fell ill Wednesday while eating dinner at the government-run sports center in Alappuzha where they were undergoing training in kayaking and canoeing, according to the Hindustan Times. Police told the Indian paper that the teenagers had left a suicide note suggesting they’d been driven to commit suicide by pressure from older athletes and trainers. Family members added that their daughters had been harassed and abused by coaches.

The warden of the hostel where the rowers lived denied the accusations.

“None in the hostel tortured them,” she told the Times of India.

Alappuzha Police Chief Suresh Kumar had been told that the teenagers were caught consuming beer over the weekend and had been “scolded” by their warden and older athletes, he told the New York Times. Their suicide note referred to “some minor fault” that was given “undue importance” by the seniors.

The young women were among thousands of athletes who attend similar training centers run by the Sports Authority of India all over the country. For many, success at the centers is seen as a pathway out of poverty.

That seems to have been the case for 15-year-old Ramabhadran (some reports have also put her age at 17). Her cousin Lincy Viju told the New York Times that Ramabhadran came from a nearby farming village and that her family struggled to live on Ramabhadran’s mother’s wages from her job as a community health worker.

“The only reason she joined the center is because they were poor, and there was no other way for her to get a job,” Viju said.

Injeti Srinivas, the director general of the Sports Authority of India, said that the organization would investigate the poisonings and the athletes’ motivation for eating the dangerous fruit.

“We have 10,000 children like this,” he said at a news conference, according to the New York Times. “They are our wards. And when an incident like this happens in our own premises, it is a matter of serious concern for us.”

India has seen cases like this before. In 2012, seven young women at an academy in another district of Kerala reportedly tried to kill themselves by eating fruit from “the suicide tree.” According to the Indian newspaper the Asian Age, the women had been caught cutting classes and attempted suicide out of fear of punishment.

In fact, women make up most of the victims of the “suicide tree,” according to the 2004 study of the toxic plant. Toxicologists told Agence France-Presse that between 70 and 75 percent of those who use the fruit to commit suicide are female, raising questions about the kinds of pressures faced by women that would drive them to such desperate measures.

The plant’s lethality comes from the toxin in its seeds. Typically used to produce rat poison and deodorant, in humans the chemical disrupts the heartbeat and can cause the heart to stop entirely. The plant is little studied or understood, according to researchers, and Srinivas told the New York Times that there is “no real antidote.”

The Alappuzha hospital is working to save the remaining three girls, Srinivas added, calling the incident “the most shocking and tragic” in his organization’s history.