Doctors say an Indian woman who was gang-raped on a bus in New Delhi earlier this month has suffered "significant" brain injury and is fighting for her life.

The 23-year-old woman was flown to Singapore for treatment at Mount Elizabeth hospital on Thursday, 10 days after she was brutally attacked by six men on Dec. 16.

Hospital chief executive Dr. Kelvin Loh said Friday she also has infection of the lungs and abdomen. He said she "is currently struggling against the odds."

He says a multi-disciplinary team of specialists is working tirelessly to save her life.

The rape has triggered widespread outrage and calls for ensuring the safety of women who are subject to sexual harassment ranging from groping to rape every day across India.