Jahi McMath, an Oakland teenager who was declared brain dead after tonsil surgery in 2013, died June 22, her mother told The Los Angeles Times. She was 18.

"Jahi died as the result of complications associated with liver failure" according to a statement from the family's attorney, Christopher Dolan, who said that McMath died in New Jersey, the East Bay Times reported.

McMath was 13 when she underwent surgery to treat sleep apnea. Doctors removed her tonsils, adenoids and extra sinus tissue on Dec. 9, 2013. According to her family, McMath began to bleed while still in intensive care and went into cardiac arrest, CNN reported.

Three days later she was declared brain-dead but her parents disagreed, CNN reported.

The family then battled the hospital, which wanted to remove McMath from a ventilator. Her family argued that she showed signs of life and should remain on the ventilator, CNN reported.

McMath was released from the hospital in January 2014. Her family flew her to a hospital in New Jersey and she later received care at a home in that state, the Times reported.