NEW DELHI (AFP) - Indian authorities launched an investigation Thursday after a young female athlete apparently killed herself by eating poisonous fruit in a suspected suicide pact following alleged harassment at a state-run sports facility.

Police said one girl had died and three others were left in a critical condition after deciding to commit suicide together following harassment at a water sports centre in south India.

The girls were found in an unconscious state at a hostel after eating a toxic fruit before being rushed to hospital, police said.

Officers said they had found a suicide note signed by the girls, all aged under 15, in which they complained about being picked on by "seniors" at the Alappuzha training facility in Kerala state.

It didn't specify whether they were talking about older colleagues or coaches, police said.

M V. Sureshkumar, the police chief of Alappuzha district, told AFP that the girls had written that they were being given a hard time for "small mistakes".

"We will be taking a statement from the girls once they become stable. We are investigating but no case has been filed as of now," Mr Sureshkumar added.

Indian Sports Minister Sarbananda Sonowal said he had asked the Sports Authority of India (SAI) to investigate the incident.

"I would only like to say that if anyone from Sports Authority of India is found guilty in connection with this tragic incident, strictest possible action will be taken against him or her," the minister said in a statement.