A woman arrested in Osaka on Wednesday on suspicion of defacing traffic signs with artsy, humorous stickers has admitted to vandalism, police said.

“I did it as a form of artistic expression but now I deeply regret it,” police quoted 43-year-old Mami Urakawa as saying.

Urakawa’s apparent accomplice, French national Clet Abraham, who describes himself as a street artist, was not detained. Within hours of Urakawa’s arrest, her photo appeared on Abraham’s social media accounts.

In a comment posted on Wednesday evening, Abraham suggested that Urakawa was his partner both in crime and life. Both claim to be residents of Florence, Italy.

“Arrested by Osaka police Clet’s girlfriend,” he declared in a post on Facebook. “In Japan it’s a crime to have a relationship with a street artist,” he added.

Urakawa is suspected of breaking the road traffic law by altering several road signs in Chayamachi, in Osaka’s Kita Ward, at around 1 a.m. on Jan. 3.

Apparent surveillance footage obtained and broadcast by Japanese media appears to show two individuals climbing a post to reach the sign. Police are thought to have identified Urakawa from the video.

Abraham earlier told his Facebook followers he was in Japan over the New Year’s holidays. Osaka police have not confirmed the second suspect’s identity but say the investigation is ongoing.

“If police ask me whether I did it, I would say ‘Yes,’ ” the Fuji News Network television channel quoted the culprit as saying, although it stopped short of naming the individual as Abraham. He told the network that he had tampered with 90 signs in Japan on the grounds that they are symbols of authority that he seeks to challenge through art.

FNN showed examples of the sticker graffiti, including images of a sign that had been altered to look like an arrow piercing a heart, and one that showed a bar being eaten by Pacman, the video game character. Other designs seemed more whimsical.

A spokesman for the Osaka Prefectural Police told The Japan Times the street sign in question was an arrow indicating a one-way street, and that altering it would have put drivers at risk of an accident. The sticker made the tip of the arrow appear warped.

Media reports say there have been 32 reported instances of road signs obscured by stickers in Osaka and about 30 in Kyoto Prefecture. There have been no reports of the signs disrupting traffic.

Abraham has gained fame and notoriety for his Keith Haring-esque sticker street art. The longtime resident of Italy is reported to have brought his guerilla graphics to cities across Europe, changing road signs in the middle of the night.

One sign he altered in Europe showed Jesus Christ crucified on a dead-end sign.

His mischief has landed him in trouble, the British newspaper the Daily Mail reported two years ago, citing reports that on at least one occasion he was fined.