Naomi Campbell underwent emergency surgery in a São Paulo hospital Monday night.

The model flew into the city on Sunday and underwent a four hour and 40 minute operation between the hours of 10pm Monday and 2:40am Tuesday.

She underwent a laparoscopic surgery of the abdomen, according to her doctor, José Aristodemo Pinotti. The procedure took place in the Sírio Libanês Hospital, a leading private hospital in São Paulo, a city Campbell visits frequently.

"I am not authorised to reveal what Naomi had, nor the seriousness," said Doctor Pinotti to the Estadão newsagency.

"I can say that I operated yesterday (Monday) and she is completely cured. It was an emergency operation, but went well. There were no incidents or any problems that had me worried during the surgery."

"The whole procedure was done using laparoscopy, without having to undergo the traditional method, which would be to open the stomach."

Dr Pinotti said Campbell woke up Tuesday morning. "I've even allowed her to sit up in bed." An infectologist David Uip is supervising the model's recovery which will include a post-op diet of liquids.

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