Three fresh arson charges have been levied against the UC-Irvine professor Wednesday who was earlier charged with setting five arson fires.

Prosecutors say he wrote lurid emails threatening to go on a shooting rampage at his dead son's school after the 14-year-old boy's suicide. The professor's son allegedly committed suicide after being disciplined at school.

Rainer Reinscheid, 48, an associate professor of pharmaceuticals at the University of California, Irvine was arrested last month after police said they found him trying to set a fire in the park where his son, Claas Stubbe, hanged himself in March, is now charged with eight counts of arson and one count of attempted arson.

Authorities said the emails, discovered after Reinscheid's arrest, described in graphic terms his plans to burn down Stubbe's high school, kill administrators and commit violent sexual assaults before killing himself.

"The emails that the defendant sent to himself and to his wife suggest that he's angry over his son's suicide and that is why he is setting these fires as well as planning to murder school administrators and students," Orange County District Attorney's spokeswoman Farrah Emami said.

Orange County prosecutors say they have not charged Reinscheid over the emails as he did not send them to the intended targets.

Reinscheid made a brief court appearance in Orange County Superior Court in Newport Beach on Wednesday, wearing a yellow jail jumpsuit, but a scheduled arraignment was delayed until next week after the new charges were filed.

He spoke in court only to agree to the postponement.

Prosecutors also amended a motion they had filed asking that Reinscheid be held without bail, saying a search of his computer showed he had conducted Internet searches for guns, gun laws, ammonium fertilizer, ammonia and car explosions.

His son committed suicide in March after he was given trash pick-up duties when he was caught stealing an item from University High's parent-run student store.