Like many famous works of art before it, a colorful mural that dominates a park across from Boston's main train station has stirred some controversy.

The 70-foot-by-70-foot (21-metre-by-21-metre) painting by Brazilian twin brothers Otavio and Gustafo Pandolfo, known as Os Gemeos, depicts a character wearing bright, mismatched clothes, his face wrapped in what appears to be a scarf except for his squinting eyes.

The work, which will be exhibited until November 2013, became a flashpoint when a local Fox television station quoted passersby criticizing the masked cartoon-like figure, which some found menacing, saying it should be removed.

The mural is painted on an air intake structure on the Greenway in downtown Boston's Dewey Square. The giant piece by Os Gemeos, which is Portuguese for "The Twins," is part of their first solo U.S. exhibition, now on display at the nearby Institute of Contemporary Art/Boston.

Jill Medvedow, director of the museum, played down the controversy. "This work of art is a joyful addition to Boston's skyline. With tremendous mastery of scale, painterly skill and vibrant patterning, Os Gemeos brings urban energy and a rich tradition of Brazilian creativity to Dewey Square in Boston. Good art gets people talking," she said.

Boston Mayor Thomas Menino also tried to defuse the issue.

"We don't need somebody out there to divide us and saying that's a racist thing, that's against a religion. It isn't," he said. "That was made to show a young boy out there and that's what I believe it is."

The mural was funded by the Institute of Contemporary art and private donations to the Rose Kennedy Greenway Conservancy, an organization that takes care of five of the city's parks including the one at Dewey Square.

Residents enjoying themselves on the Greenway on Wednesday, where the band Receita de Samba provided additional Brazilian flavor, mostly praised the work for its originality and beauty.

"It's nice," said Loreno St. Dubois, a 58-year-old postal employee from South Boston, who added that he could understand the negatives reactions to it.

Ben Gebo, 27, a freelance photographer hired by the conservancy to document the mural's creation, said as the piece was painted its meaning changed.

"I see it as an interesting artwork. I'm still not exactly sure what it's supposed to be," he said. "It's really up to the eye of the beholder. It definitely draws attention and gets people talking, which I think is the important thing."