WASHINGTON (AP) — Vandals spray-painted dozens of swastikas on the outside of Union Station, the central hub for regional train transportation in the nation’s capital.

The graffiti was discovered Friday, a day after International Holocaust Remembrance Day, with crude Nazi symbols painted on columns across the front of the massive building and several clustered around the escalator entrance to the underground D.C. Metro.

Washington’s Metropolitan Police Department referred questions to the Amtrak Police, which handles security for the building. Efforts to contact the Amtrak Police were unsuccessful. But a security guard on the scene, speaking on condition of anonymity, told The Associated Press that the incident was under investigation. The guard pointed out that several of the swastikas were painted in spots that were in full view of the building’s security video cameras.

By midday, staff had begun to cover the swastikas with sheets of white paper secured by blue tape.

The Jewish Federation of Greater Washington posted a statement on Instagram, calling the timing “particularly offensive” and added, “This anti-semitic and hateful symbol has no place in our society.”

It is unclear whether the connection to International Holocaust Remembrance Day was intentional.

The Jewish Federation’s post indicated that police had provided them with some information about the suspect.

“We have learned that the person involved is homeless and a mental wellness services consumer, and we are relieved to know it will be removed as soon as possible, ” the message said.