Masked naked man strikes again near Yonsei University trail — and no one was watching

"According to the victim, the naked man was tall and seemed young."

A series of sexual assaults by an unidentified masked man wearing nothing else has been reported in and around Ansan in Seodaemun-gu, Seoul. Following incidents in June and July, another attack occurred around 10 p.m. Wednesday on the Yonsei University campus, sending both nearby residents and students into a state of fear. Police believe the three incidents are likely the work of the same person given the similar pattern, but have yet to identify a suspect.

Even after the attack, the entrance connecting Ansan to the Yonsei University dormitory area remained open, allowing outsiders to enter freely — yet no police officers or university security personnel were visible to guard against any further incident.

A reporter visited the scene of the on-campus attack and the Ansan trail around 11 p.m. Thursday, where they met Choi, 49, a local resident who had an indirect encounter with the case. Choi had happened upon the victim of the July attack and heard firsthand what had happened.

Choi, who walks through Ansan every day, was heading up from Hongjecheon stream to Ansan with a group on the day of the July incident when they encountered the victim coming down the mountain in distress. "A woman who looked to be in her late twenties came running down the mountain in tears," Choi said. "Some of the women in our group tried to calm her down."

Choi said the victim described how a hand had come from behind her, reaching far above her own shoulder height, and that the attacker's description — a mask and nothing else — matched the Wednesday incident as well. Choi's group had asked the victim for a detailed description of the man's appearance while searching the mountain to report him.

"She said he ran naked into the bushes," Choi said. "And apparently he darted back into the bushes very fast, so she thought he seemed young."

Another local resident, Seo, 61, said: "Ansan has CCTV cameras installed all over the place, and the fact that he still hasn't been caught makes me think this is someone who knows every corner of the area."

The Seoul Seodaemun Police Station, which is handling the case, also believes the suspect is someone well acquainted with the area. Based on analysis of CCTV footage obtained so far, police estimate the suspect stands between 160 and 170 centimeters tall and is likely in his 40s or 50s — a description that differs from what Choi heard from the July victim. Investigators say multiple possibilities remain open at this stage.

Police have struggled to identify a suspect for more than two months since the first report was filed on June 12. "There aren't many CCTV cameras along the trail to begin with," a police official said. "And if he had been wearing clothes, identification would have been much easier — but with just a mask and nothing else, it's very difficult to pin him down."

Students passing near the Yonsei University dormitories late Thursday expressed anxiety, but getting help quickly in an emergency would have been difficult. During the roughly one and a half hours a reporter spent at the scene, no police officers, university security guards, or any other patrol personnel were encountered near the dormitories or along the Ansan trail. The security booth at the north gate entrance — the gateway to the dormitory cluster — sat empty the entire time.

The alley near the tennis courts leading to dormitories 1, 2 and 3 borders Ansan directly, and just a few steps beyond the reach of the streetlights, the darkness was absolute. Areas the lights did not reach were effectively invisible, with objects as close as about 8 meters impossible to make out clearly.

Students returning late used their phone flashlights to navigate the dark stretches, or arranged to walk in with friends at a set time. Kim, 23, was walking arm in arm with a friend after getting off a shuttle bus near the dormitory.

"Posts have been going up on the school community board and it's been in the news all day, so I'm anxious," Kim said. "It's a path I walk every day, but it feels eerie and scary. Tonight I arranged to come in together with a friend."

Most students were already aware of the incident. Jeong, 26, a fourth-year student in the College of Liberal Arts, said he knew an attack had occurred near the dormitories. "The gate from Ansan is left open, and there's a restaurant open to the public in dormitory 2, so outsiders come onto campus quite often," he said.

Thursday, Yonsei University issued a notice on enhanced security in the dormitory zone, announcing measures that included closing the rear entrance of Muak Dormitory 1, adjusting the brightness of streetlights along walkways, and strengthening patrol operations.

The measures, however, fell short of fully easing students' fears. While the university closed the Muak Dormitory 1 entrance that day, another gate near the dormitories remained open.

That gate connects Ansan to the Yonsei campus, leaving it possible for outsiders to enter through the mountain at any time. During the reporter's time on scene, at least one outsider was observed entering the campus from Ansan through that gate.

No patrol personnel were encountered in the alley beyond the barricade at that entrance leading toward the dormitories, and the nearby north gate security booth remained empty throughout the reporter's visit.

A Yonsei University official said the security booth had been empty because guards were out on patrol at the time. "That zone is not covered by foot patrols, but it is monitored through video equipment," the official said.

On the open gate, the official said the entrance near the scene of the attack — the Muak Dormitory 1 gate — had been closed, while the other gate was left open for students' use. "Closing it would also generate complaints from students, so we kept it open," the official said.

The attack occurred on Wednesday, and with a suspect still unidentified, no police were visible at the scene Thursday night. Police announced security measures Friday, two days after the incident.

Seodaemun Police Station chief Lee Sun-myeong visited the Yonsei University Muak dormitory area and the Ansan trail Friday to inspect the crime scene and assess the surrounding security situation. A police official said the station had decided to deploy a wide-area crime prevention patrol unit to the area.