A 57-year-old man admitted during the first court hearing of his case Thursday to trespassing and other charges over an incident last April in which knives were found on Prince Hisahito's desk at a Tokyo junior high school.

Kaoru Hasegawa, a resident of Kyoto, said there was "no mistake" in the allegations presented against him at the Tokyo District Court.

The imperial succession on May 1 last year promoted Prince Hisahito to second in line to the chrysanthemum throne after his father Crown Prince Fumihito, 54, the younger brother of the 59-year-old emperor.

The trial concluded later in the day with prosecutors seeking an 18-month prison term, and the defense team requesting a suspended sentence. The court will deliver its ruling Feb. 14.

Prosecutors submitted two knives with their blades stained pink as evidence, saying the defendant "had always held a personal interest in the imperial system."

"His motive was to draw public attention," they said.

Hasegawa apologized, saying his actions were "reckless" and "unforgivable," but he did not mention the imperial family.

According to the indictment, Hasegawa used pruning shears to cut the cable of a security camera installed on the grounds of Ochanomizu University Junior High School on April 26, 2019. Carrying two knives with blades of around 11 centimeters each, he then entered the school's grounds disguised as a contractor.

Later that day, a teacher found an aluminum bar with the two knives attached by duct tape placed across the prince's desk and the one next to it. The 13-year-old nephew of Emperor Naruhito and his classmates were not in the classroom at the time.

The defendant, who was arrested three days later, told investigators he is against the imperial system and intended to stab the prince.