UPDATE 1-Soccer-Flare kills Bolivian boy at Libertadores Cup match

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* Corinthians fans arrested after incident in Oruro

* Doctor says 14-year-old's death was immediate

Feb 21 (Reuters) - A 14-year-old Bolivian boy was killed by a flare allegedly launched by Corinthians fans during a South American Libertadores Cup match in Oruro, Brazilian and Bolivian media reported on Thursday.

The incident, in which the boy was hit in the eye and died almost instantly according to the doctor who attended to him in hospital, occurred during a 1-1 draw between Bolivia's San Jose and Libertadores Cup holders and world club champions Corinthians on Wednesday night.

"There was a loss of brain matter as the projectile, a plastic tube, penetrated the (boy's) skull. Due to this, death was immediate," doctor Jose Maria Vargas told local media at the Hospital Obrero in Oruro according to Brazil's Globo.

Bolivian media identified the boy as Kevin Beltran, a San Jose fan, who was hit by the flare minutes after Corinthians took an early lead through Paolo Guerrero, the Peru striker who scored the winner against Chelsea in the Club World Cup final in Japan in December.

Witnesses told local media the flare came from a sector occupied by Corinthians fans. Many San Jose supporters, who team equalised through Carlos Saucedo after an hour, left the Jesus Bermudez stadium in Oruro in tears on hearing about the incident.

Corinthians coach Tite told reporters: "I would exchange my world title for the boy's life.

"I'm sorry about what happened tonight. We can't talk about football, it's my feeling and that of the players, we couldn't utter a word in the dressing room," he told a news conference.

"Corinthians is available to try to help in whatever way with what happened... I didn't want to be here (at the conference), what happened is too heavy to be able to talk of football, I'm sorry," he added and left the room.

A dozen Corinthians supporters identified by Bolivian police were arrested and a spokesman for San Jose said a criminal investigation would be opened, match broadcasters Fox Sports reported. Police kept fans of the rival teams apart on leaving the stadium.

Brazilian media also reported Corinthians could be kicked out of the competition if it was confirmed some of their fans were responsible for the boy's death. (Writing by Rex Gowar in London, editing by Pritha Sarkar)