ANN ARBOR, MI - Racist graffiti discovered on a mural in downtown Ann Arbor washed away easily enough on Sunday, Sept. 17, but the hateful attitude conveyed disturbed artist Mary Thiefels even after the paint was gone.

The words "Free Dylann Roof, I Hate N******" were painted in red over a mural that stands in an alley off the 600 block of East Liberty Street, on the side of the building that formerly housed Borders and now is the site of Pieology.

Roof, 23, is a white supremacist and mass murderer who killed nine people at a church in Charleston, South Carolina, in 2015.

"My heart was broken, in the fact that that is an ideology and a sentiment that people feel strongly enough to share with the world," said Thiefels, who designed the mural in 2014. "At the same time, things like this create dialogue that is so important and so relevant to right now. ... Who knows if it will inspire a productive conversation or if it will just create more divide."

Thiefels said her sister alerted her to the vandalism around 10:30 p.m. Saturday. Ann Arbor Police took a report on the incident Sunday morning, said Sgt. Travis Strang, and no further details on the incident were available from police as of Sunday afternoon.

By 12:20 p.m. Sunday, Thiefels and her neighbor Crystal Conway had washed away the graffiti after about an hour of scrubbing the brick wall. Conway said they wanted to wash away the graffiti quickly so the person responsible wouldn't have the satisfaction of coming back to see it.

"I was like let's just take action," said Conway, who owns Lady MacGyver landscaping. "Let's not leave that up for more people to feel disturbed. ... Letting whoever this is (who painted the message) travel back here and revel in the idea that it's still there, now they don't get to."

The mural features a geometric box pattern at either end that gives way to an image of hot air balloons floating through the sky. The piece was commissioned as part of a shur! "Work, live, play better" series, and about 50 community members painted it in one day.

"We ended up creating that mural as a physical expression of what it meant to embrace your own agency and create something positive in the community," said Omari Rush, who organized shur! and is the former vice president of strategic initiatives at the Ann Arbor Art Center.

Rush was in Denver when he got the news the mural had been vandalized, and he hopes the hateful message will serve as a call to action for people to continue finding ways to make the community better.

"People have their right to feel and say whatever they want to say, but there's just no place for that (type of graffiti) in a community that is trying to be a place that is inclusive, that's trying to be accepting, that's trying to be a place where everyone can thrive and prosper," Rush said. "This is just in my mind yet another call to action. It's yet another reminder of all the work that we have to do in the realm of education and the areas of social services. We all have to be working to make our community better, and it's going to take everybody being part of that."

Thiefels said she will have to refurbish part of the mural that was damaged by washing away the graffiti. There have been other times her public art has been tagged by a graffiti artist, Thiefels said, and she left the tag as a type of "collaboration" between the graffiti artist and her original intent for the piece.

But this vandalism was different.

"Every project like this out in the community is subject to interpretation, to criticism, to vandalism," she said. "It's definitely been hard to swallow, but also it's making a very important point that hate speech is real. The lid is off."

Anyone with information regarding this incident can contact the Ann Arbor Police Department tipline at 734-794-6939 or email tips@a2gov.org.