Burbank Police are investigating the death of a 16-year-old male following some sparring at Pullman's Gym on West Magnolia Boulevard on July 26, 2012.

Burbank Police are investigating the death of a 16-year-old male following some sparring at Pullman's Gym on West Magnolia Boulevard on July 26, 2012. (Ross A. Benson / September 25, 2012)

The death of a 16-year-old North Hollywood boy who collapsed after a sparring match in a Burbank boxing gym was ruled an accident, coroner’s officials said.

Raul Alvarez Jr. died of massive internal bleeding and a ruptured spleen, which tore during the sparring session, according to Ed Winter, Los Angeles County's assistant chief coroner. Raul also suffered from infectious mononucleosis, he added.

He was rushed to Providence Saint Joseph’s Medical Center on July 26 after complaining of pain at Pullmans Gym on the 4300 block of Magnolia Boulevard.

At the hospital, Raul suddenly fell unconscious and died, police said.

The teen was wearing protective gear on his head and lower body when he sparred with another boxer of about the same age and build at the gym, police said.

Gym staffers were also monitoring the match.

An employee at Pullmans on Tuesday said the manager and owner were unavailable for comment because they were traveling with a boxer.

-- Veronica Rocha, Times Community News

Follow Veronica Rocha on Google+ and Twitter: @VeronicaRochaLA