An anti-Islam group filed a civil rights lawsuit against New York City's Metropolitan Transportation Authority (MTA) on Wednesday for refusing to run a "Hamas Killing Jews" advertisement on city busses, the group's attorney said.

The American Freedom Defense Initiative claims the state agency violated its constitutional rights by turning down advertisements that included the slogan, "Killing Jews is worship that draws us close to Allah — Hamas MTV," the lawyer said.

David Yerushalmi, lawyer for Pamela Geller, whose group is sponsoring the ad, said in a statement the MTA banned the advertisements because they threatened to incite violence.

The MTA denied comment on Wednesday, citing pending litigation.

Geller writes a blog criticizing Islam. Her group paid for a six-ad series scheduled to run for a month on the city's mass transit system.

"When our clients run ads exposing this Jew hatred, all of a sudden the transit authorities are worried about the 'tone' of the conversation or conjure up some threat of violence," Yerushalmi said.

He said the MTA has allowed what he termed misleading advertisements sponsored by Muslim groups.

Earlier this week, Geller agreed to remove a photo of American journalist James Foley, taken shortly before his beheading, scheduled to appear on advertisements on 100 New York City buses and two subway stations.

The removal followed a plea from Foley's mother to remove the image and criticism from city politicians and religious leaders who said no faith should be subject to attack ads and calling it an attempt to divide the city.

Geller was behind a similar ad campaign in 2012 on the city's transport system that the MTA originally rejected. A federal judge later decided that the state agency's rule against ads that demeaned race, gender, religion or several other categories was unconstitutional.