ROME—Richard Meier’s controversial modernist design for the Ara Pacis Museum has been criticized for clashing with this ancient city’s classical architecture. Now the building has become the target of vandals, who overnight threw paint-filled balloons against the outside white wall, splashing it with the red and green colors of the Italian flag. They also left a porcelain toilet and two packs of toilet paper next to the museum, which sits on a Fascist-era piazza in central Rome.

The white, block-like structure was assigned to the famous U.S. architect in 1998. Rome’s mayor says officials are talking with with Meier to discuss changes to the building to "improve its urbanistic impact." Meanwhile, no one has claimed responsibility for the vandalism, police said, and on Monday the splashes were being painted over.

Read more at the Associated Press.