A South Korean man arrested in connection with a suspected bombing at Yasukuni Shrine in Tokyo late last month admitted to police that he set explosives at the compound, but later denied doing so, Japanese investigative sources said Thursday.

Chon Chang-han, 27, who was arrested Wednesday on the technical grounds of entering a premises for unlawful purposes, now denies having set an explosive device at the shrine’s public restroom, which apparently failed to activate although people who were there at the time heard the sound of an explosion.

The police will continue their investigation, believing the man intended to cause an explosion at the Shinto shrine, viewed by neighboring Asian countries as a symbol of Japan’s militarist past.

Chon had flown to Japan on Nov. 21 and returned to South Korea on the afternoon of Nov. 23, the day of the suspected late morning bombing. There are no records of the suspect having visited Japan before that.

He then flew back to Japan on Wednesday, which sources close to the matter have said was of his own volition and that South Korean authorities were not involved. Chon was arrested at a police station in Tokyo later in the day.

The sources said Chon followed police instructions that day without resisting and that his cellphone and other belongings were confiscated.

Chon initially denied the allegation, but then he told the police, “I entered Yasukuni Shrine on the 22nd and 23rd (of November) and set explosives on the 23rd.” The remarks, however, were retracted, according to the sources.

The South Korean man emerged as a suspect as he was caught on surveillance camera footage before and after an explosion was heard at about 10 a.m. on Nov. 23 at the men’s restroom of the shrine.

The blast was heard when about 100 people were visiting the main shrine building for a religious festival that had just started, but no one was injured in the incident.

On the floor of a stall in the restroom was a digital timer, and batteries with Hangul letters were also left scattered around. Metal pipes, containing a granular substance presumed to be gunpowder, were found in the ceiling. These items are believed to have been part of an explosive device.

DNA detected from a cigarette butt found at the restroom was identical to that detected from items left at a Tokyo hotel room where Chon was staying during his visit to Japan last month.

He has told police that he returned to Japan to “see the restroom” after being linked to the incident and contacted by some Japanese and South Korean media in South Korea. Chon had booked a ticket to fly back home later Wednesday.

The Shinto shrine has long been at the center of diplomatic friction, particularly with China and South Korea, whenever high-ranking Japanese politicians pay homage there as it honors convicted war criminals along with around 2.5 million war dead.

South Korea’s Foreign Ministry said Thursday that it has lodged a protest with Japan over local media’s reporting on the arrest, which revealed the identity, face and photo of the suspect.

In Tokyo, Chief Cabinet Secretary Yoshihide Suga denied the Japanese government’s involvement in the media reports.

“I’m not aware of” Seoul’s protest, Suga said at a news conference. “But there is no way that police would provide (the media) with a photo of the face (of a suspect).”