BEIRUT — A multi-day international music festival in Lebanon said Tuesday that it's canceled a planned concert by a popular Mideast rock band whose lead singer is openly gay, apparently caving to pressure after weeklong calls by some Christian groups to pull the plug on the show, as well as online threats to stop it by force.

Festival organizers released a statement saying the "unprecedented step" of canceling the performance by Mashrou' Leila was done "to prevent bloodshed and maintain peace and stability."

"We apologize for what happened, and apologize to the public," it added.

Some church leaders and conservative politicians set off a storm of indignation on social media this week when they demanded that the Mashrou' Leila concert be canceled, saying some of the group's songs are an insult to Christianity. The band, known for its rousing music and lyrics challenging norms in the conservative Arab world, soon became the center of a heated debate about freedom of expression.

Online, some groups and users posted veiled threats suggesting they would violently stop the concert.

Mashrou' Leila was scheduled to perform in the coastal city of Byblos on Aug. 9, marking the third time the group takes part in the annual Byblos International Festival. The other performances will still take place.

The cancellation triggered a storm of protests and a campaign of solidarity with the band on social media by Lebanese who described it as shameful and a dangerous precedent.

"This is a step back for Lebanon, which has always prided itself on embracing diversity and being a center for music, art and culture," tweeted Aya Majzoub, a Lebanon researcher at Human Rights Watch.

There was no immediate comment from the band, which last week issued a statement denouncing the "defamatory campaign" and saying that some of the lyrics from their songs were being taken out of context and twisted.

The group has been a champion of LGBT rights in the Arab world and regularly sings about controversial subjects such as sectarianism, corruption and other social problems.

The band has previously been banned from performing in Jordan and Egypt, but censorship demands threatening its concert in the more liberal Lebanon — where it has performed on numerous occasions — are new.

On Monday, dozens of Lebanese held a protest in downtown Beirut objecting to the proposed ban and rejecting attempts by Christian clergymen and some right wing groups to ban the group.

"Regardless of our opinion of the songs and the band, we need to defend freedom of expression, because freedom is for everyone and for everybody. The day it stops, it stops for everybody," said writer and director Lucien Bourjeily.

The band, whose name translates as "Night Project," was founded 10 years ago by a group of architecture students at the American University of Beirut whose songs challenged stereotypes through their music and lyrics.

Riding on the wave Arab Spring uprisings that swept the Middle East, the band was embraced by Arab youth who see its music as part of a cultural and social revolution. The band members have gone on to gain worldwide acclaim, performing in front of sold-out crowds in the United States, Berlin, London and Paris.

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