(Recasts with fan sacking, adds background, quotes)
By Andrew Downie
SAO PAULO, Aug 29 (Reuters) - A Gremio fan lost her job on Friday and could face criminal proceedings after she was caught racially abusing a Santos player during a Brazilian Cup match, police said.
The young woman, who was not identified by authorities, worked at a police hospital in Rio de Grande do Sul state, home of the Gremio club.
The woman was filmed shouting "Monkey" at Santos goalkeeper Aranha during Thursday's match at the Gremio Arena, a new stadium opened less than a year ago.
"The fan filmed yesterday abusing the Santos goalkeeper was removed from her position at the clinic," tweeted the local police force, known as the Military Brigade.
"The fan was an employee of a company hired to provide services to the Military Brigade's clinic," the police added. "The Military Brigade repudiates any racist attitudes."
The woman and other Gremio fans taunted Aranha during Santos's 2-0 first-leg win. Gremio apologised to the keeper and said they had launched an investigation.
"The club's legal department, in conjunction with the administrators of the Arena, are taking every measure possible so that the people involved in this episode are identified and so that all materials at our disposal are sent to police in order for them to launch appropriate criminal proceedings," the club said in a statement on their website.
Gremio said the offensive supporters were in no way representative of the club and promised to ban anyone found guilty of racism.
Santos called the attacks "inadmissible" and although acknowledging the abuse was isolated, the club said it was impossible to ignore.
Aranha was clearly upset at the abuse and his team mates and manager said it could have had an impact on the result.
"We need to inhibit this kind of act, because if we don't then we are in a way condoning it," Santos said in a statement.
Aranha added: "The only word I have for this is disappointment.
"Today, I was the victim. But this has happened before and it will keep happening if we don't take action to stop it."
The club said they would take "appropriate measures" without specifying what they would be.
The episode was the latest in a string of unsavoury incidents to taint Brazilian football.
Gremio were fined 80,000 reais ($35,800) in April after fans racially abused an opponent during the local derby with Internacional.
Santos's midfielder Arouca was racially abused this year by fans of Mogi Mirim after a Paulista state championship game. Authorities closed the Mogi stadium for several matches.
Racism is a criminal offence in Brazil but few people are charged and even fewer are jailed.
Around six percent of Brazilians class themselves as "black". A majority of the country's 200 million people consider themselves to be "dark-skinned". ($1 = 2.2366 Brazilian Reals) (Editing by Ed Osmond and Toby Davis)