A 26-year-old Pearl City man has been charged with sending threatening emails to two college professors.

Neill O. Tumulac was charged this week with violating interstate communications laws in connection with the emails. He made his first court appearance in federal court Wednesday.

Tumulac’s next hearing is scheduled for Tuesday. He is being held at the Honolulu Federal Detention Center after federal agents arrested him Wednesday at his Pearl City home.

Court documents said Tumulac was enrolled at a college on Oahu in the spring. He allegedly sent more than 130 emails to one of the professors from February to mid-October, a majority of which were sent from his personal email account and approximately a dozen sent from his college email account.

The content of the initial emails initially sent the teachers was described as bizarre and included accusations of “mental manipulation.”

Later emails became more hostile. In one he told a professor “you will die a painful death” and “you are a dead man.” Other messages to the same professor contained racial and homophobic slurs.

Court documents said the professors filed a request for a temporary restraining order against Tumulac in July, but the court dismissed it without prejudice because Tumulac reportedly moved to Las Vegas.

But the digital menacing continued. In August, Tumulac allegedly sent one professor an email in which he repeatedly wrote, “I will (expletive) murder you,” emphasizing the threat with capital letters.

Court documents said the emails distressed the professor, prompting him to keep a knife under his bed and install a security video surveillance camera at his residence.

The other professor said the emails caused her to be “constantly on edge worrying Neill might do something violent.”

During an investigation, federal agents discovered YouTube videos allegedly posted by Tumulac that contained homophobic slurs. The videos have since been removed.

Court documents also indicated Tumulac underwent a psychiatric evaluation in June 2017 after his father reported to Honolulu police that Tumulac threatened to kill him.

In September while Tumulac was in Las Vegas, police took him to a hospital for a psychiatric evaluation after they found him slashing the walls of his apartment with a sword.

Las Vegas police found substances in the residence believed to be ingredients to make heroin. Court documents said Tumulac told police he was trying to make DMT, a hallucinogenic drug.

Laboratory test results on the substances are pending.