NEW YORK—Police have arrested a New York couple on graffiti charges and say they suspect the couple tagged up all over Europe this summer, too. The Associated Press reports that Jim Clay Harper and Danielle Bremner are believed to have written their tags — "Ether" and "Dani," respectively — on train cars in London, Madrid, Paris, Frankfurt, and Hamburg. Police arrested them on their return.

The warrant for Bremner alleges a graffiti spree that caused tens of thousands of dollars in property damage to New York's transit system. The charge is a felony because of the high degree of damage. Harper was brought up on related charges of felony criminal mischief and burglary last week and pleaded not guilty. If convicted, each could face up to seven years in prison.

The NYPD has said it will share information with European authorities if they want to bring cases against Bremner and Harper for their graffiti abroad. Police also said the couple could face additional charges for tagging New York subway trains that were parked overnight.

Bremner, 26, is a New York native and a graduate of the Fashion Institute of Technology who goes by the tag "Utah" as well as "Dani." She has been under investigation for almost two years and was linked in the past to graffiti in Boston and Pittsburgh, according to Sgt. Kevin Cooper, who investigated the present New York case. Harper, 23, is from Chicago and a former member of Made U Look, a graffiti crew known for covering an entire subway train with a Monopoly motif in 2006.