Two high school students and a man were wounded in a knife attack on Saturday just outside the University of Tokyo ahead of nationwide entrance exams and a teenager apparently frustrated with his academic performance has been arrested on suspicion of attempted murder, police said.

The 72-year-old man was seriously injured after he and the two students, aged 17 and 18, were slashed in the back around 8:30 a.m. in front of one of the gates to the university's main campus, according to the police.

Yellow police tape is seen at an entrance at the University of Tokyo after a stabbing incident on Jan. 15, 2022. (Kyodo)

The male and female students, both traveling from neighboring Chiba Prefecture to take the exams, did not sustain life-threatening injuries, with the police quoting the 17-year-old suspect as saying he was not acquainted with the three, who were walking on the sidewalk separately.

"I was not doing well in my studies so I wanted to cause an incident and die," said the suspect, a second-year student at a private high school in Nagoya who was not going to take the exams, after he was arrested near the university, considered one of the most prestigious in the country, according to the police.

"I was studying for the University of Tokyo to become a doctor, but my grades have been poor for a year and I lost confidence," the teenager, who has confessed, was also quoted as saying. "If I could not become a doctor, I thought I'd kill someone and carry a guilty feeling on my back while committing 'seppuku' (harakiri)."

The attacker has told the police he came to Tokyo by an express bus that was to arrive in the capital at around 6 a.m. on Saturday, an investigative source said, adding that his father notified the Aichi prefectural police on Friday night that his son was missing.

According to the police, the attacker, whose name has been withheld as he is a minor, also said he had brought the knife he used from his home in the central Japan city, about 250 kilometers away from Tokyo.

When police officers arrived, he was sitting on the ground, and the bloodstained kitchen knife, with a 12-centimeter blade, was found nearby, they said.

The police said his bag had plastic and glass bottles containing combustible liquid, adding he also had a folding saw and another knife.

The attack occurred as Japan's two-day unified university entrance exams, sat by more than 530,000 applicants, began nationwide amid concerns over the rapid spread of the Omicron variant of the coronavirus among students and their family members.

Despite the incident, the University of Tokyo, one of more than 650 test venues, conducted the first day of the annual exams as scheduled starting at 9:30 a.m.

The quick arrest was possible because the 72-year-old man from Tokyo rushed to a nearby police box, they said.

Photo taken on Jan. 15, 2022, shows an area near the site of a knife attack by a teenager just outside the University of Tokyo in the capital's Bunkyo Ward. Two high school students and a man in his 70s were wounded in the attack ahead of nationwide college entrance exams and the teenager was arrested on suspicion of attempted murder. (Kyodo) ==Kyodo

Although violent crime is relatively rare in Japan, a number of random attacks have occurred in recent months, including an arson case at a mental health clinic in Osaka in mid-December that killed 25 people.

The teenage attacker was also quoted as saying he started a fire at a station near the campus before the incident.

The Tokyo Fire Department said that it was alerted to a fire within the premises of Todaimae Station on the Namboku Line operated by Tokyo Metro Co. at around 8:30 a.m. and that it was extinguished around an hour later.

The knife attack appeared to unsettle some test-takers at the venue, to which police and firefighting vehicles were mobilized. The incident occurred outside the gate of the Yayoi section of the main campus of the university.

An 18-year-old test-taker said he learned about what happened via Twitter. "It has become a big incident and it's scary. I want to do my best in the test and not be affected," he added.

Another test-taker, an 18-year-old high school student from Tokyo, expressed her anxiety over the crime at a time when people are already feeling jittery about the coronavirus.

A woman in her 50s who accompanied her son to the exam venue said she hopes her son will not be shaken. "He studied so hard (for this) so I wanted him to be able to take the test in a good environment," she said.

The National Center for University Entrance Examinations urged the state-run, public and private universities that are the venues for the exams to beef up security measures.

The exams, conducted amid anti-COVID measures, drew 530,367 applicants and are taking place at 677 venues.

In Japan, standardized university entrance exams are held annually in two stages, with the first standardized for all universities and the second involving university-specific exams.

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