Authorities at Mumbai’s Byculla Jail on Monday ordered an investigation to check if there was any foul play by prison authorities which led to Indrani Mukerjea falling sick on Friday night.

Mukerjea, who has been in prison since 2015 in connection with the murder of her daughter Sheena Bora, was taken to JJ Hospital in Mumbai on Friday, reportedly in a “delirious condition”.

Hospital authorities said on Sunday that a “basic-level provisional diagnosis” pointed to poisoning or a drug overdose. She had undergone liver and kidney function tests, a CT scan of her brain and an ultrasound of her abdomen area. Her condition improved on Sunday, JJ Hospital Dean Sudhir Nanandkar said according to PTI.

“She is not on life-support system. She is responding to the line of treatment,” Nanandkar said. He added that Mukerjea was administered medicines orally by prison guards. He said the medicines were not given to her, nor was she allowed to store them.

Additional Director General, Prisons, Bhushan Upadhyay said Inspector General of Prisons Rajyavardhan has directed a detailed investigation into the incident, ANI reported.

Rajyavardhan said that a preliminary inquiry is already on but the authorities are waiting for a formal communication about an official investigation. He added that they are still awaiting Mukerjea’s medical reports.