A research scientist at the City of Hope National Medical Center in Duarte has been charged with making death threats against his supervisor and two colleagues.
Thomas William Balon, 49, allegedly told a fellow scientist on Nov. 1 that he was planning to kill the three men, authorities said.
Los Angeles County deputies arrested him Nov. 19 at the medical center, said Sheriff's Det. Darren Williams. City of Hope then obtained a temporary restraining order against Balon.
Balon pleaded not guilty Wednesday to three felony counts of making criminal threats. He posted a $75,000 bond and was released Thursday. A preliminary hearing is scheduled Dec. 5.