LOS ANGELES — Authorities said Friday that a Boston man who wore a bulletproof vest on a plane and had knives and other weapons in his checked bags also had manuals stored on his computer detailing how to kill people and schedules showing when pupils would arrive and leave from Japanese schools.
The disclosures were made in a court appearance by suspect Yongda Huang Harris during which US Magistrate Judge Paul Abrams declared him to be a flight risk and ordered him held without bond until he stands trial.
Federal prosecutors also argued that Harris, 28, is a danger to the community by noting that his computer contained publications outlining how to commit certain types of murders and kidnappings. One document titled ‘‘Man Trapping’’ showed how to hunt and trap human beings.
Melissa Mills, an assistant US attorney, said an examination of Harris’s computer showed he had a ‘‘strong interest’’ in sexual violence against girls. There was also a document with schedules for schools.
In his ruling, Abrams said the evidence showed Harris was not making good choices.
Harris was arrested a week ago during a stopover in Los Angeles on his trip from Japan to Boston. He was wearing a bulletproof vest under a trench coat and also wore flame-
retardant pants and knee pads.
A search of his checked luggage uncovered numerous suspicious items, including a smoke grenade, knives, body bags, a hatchet, collapsible baton, biohazard suit, billy clubs, handcuffs, leg irons, and a device to repel dogs, authorities said.
Harris is charged with one count of transporting hazardous materials, in relation to the smoke grenade, which carries a maximum penalty of five years in prison.
Defense lawyer Steven Seiden, who asked that his client be released on bail, said the clothing worn by Harris is commonplace in Asian countries and described the outfit as resembling martial arts clothing. He said the body bags were actually a large duffel bag for moving items.
Seiden said in court that Harris had been a victim of violence before — attacked on a Boston street — and he carried some of the items found in his luggage to defend himself.