OAKLAND, Calif. (CBS Sacramento/AP) — A 13-year-old Northern California girl is brain dead after going into surgery to remove her tonsils.

KGO-TV reported  Sunday that Jahi McMath’s family is demanding Oakland Children’s Hospital conduct an investigation after she went into cardiac arrest and died, before being brought back by hospital staff. Jahi is brain dead and on life support.

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Doctors said the surgery would help with Jahi’s sleep apnea, but there were complications during her recovery last week. Her mother Nailah Winkfield said Jahi had “actual clots” sliding out of her mouth, which her mother was told to catch in a cup for hospital staff to measure.

“She smiled when she walked in this hospital and I told her this surgery is to make you better,” Winkfield told the tv-station.  “My daughter went into cardiac arrest and died and they brought her back and now she’s brain dead.”

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A hospital spokeswoman said in a statement that any surgery is risky and that the hospital would investigate what happened. She didn’t provide details on the surgery.

The family is shocked and says the hospital staff is asking to consider removing the teen from life support.

“They just have a social worker follow me around all day long asking me ‘do you have any other family that needs to see her?’ like trying to put a rush on it,” Winkfield said.

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