Ramiz and Lisa, who asked that their last names not be used due to a Facebook threat against. Picture: Washington Post photo by Annie Gowen

Kolkata, India - The 21-year-old Hindu college student was having a quiet breakfast with her mother when her phone pinged with a terrifying message. Her name was on a hit list.

She and her Muslim boyfriend had been targeted publicly on Facebook along with about 100 interfaith couples - each of them Muslim men and their Hindu girlfriends. She immediately called her boyfriend to warn him.

The Facebook post included instructions: "This is a list of girls who have become victims of love jihad. We urge all Hindu lions to find and hunt down all the men mentioned here." At least two followers heeded the call.

The phrase "love jihad" is meant to inflame dark fears that Muslim men who woo Hindu women might be trying to convert them to Islam - a prejudice that the Hindu right has tried to stoke for nearly a decade. But use of the term has spread on social media with the rise of the Hindu nationalist party of Prime Minister Narendra Modi, at a time when religious hatred is growing on Facebook in India, its largest market.

Facebook is facing rampant criticism that hate speech spread on the platform has fuelled ethnic and religious violence in Asia, in places such as Myanmar and Sri Lanka.

The list of Hindu-Muslim couples was posted by Satish Mylavarapu, a mild-looking sales and marketing manager in Bangalore who propagates militant Hinduism to thousands of followers in Facebook groups and elsewhere.

The young couple's romance began in the online space that would be its unraveling. They met in 2016 through a student Facebook group for the Communist Party, which is active in some parts of India. He was immediately enchanted by her blue eyes - contact lenses - and her earrings - silver circles with a likeness of Che Guevara that she made herself.

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Their relationship soon blossomed in real life, and they met in Kolkata's tea stalls or along its lovers' riverbank promenade, Prinsep Ghat, holding hands and even kissing.

"We don't believe in religion. We believe in humanity," said Ramiz, a 26-year-old English honors student, sitting in a coffee shop with his girlfriend at his side. "So there is no question of conversion." Because of the threat, Ramiz asked to be identified by only his first name and his girlfriend by her family nickname, Lisa.

Yet tension was unavoidable in a deeply traditional society riven by caste and religion. His parents, a clerk and a social worker, grudgingly accepted their relationship, although they made it clear they prefer a Muslim daughter-in-law; Lisa's mother lent her support only if Ramiz gets a good job.

The couple, upset over the perceived threat that the Facebook hit list posed to India's secular ideals, filed a complaint with the Kolkata police's cyber division in February, saying they had been subjected to death threats.

A WhatsApp message on the phone of a Hindu activist in India's Eastern city of Kolkata warns of "love jihad" - the fear that Muslim men will seduce Hindu women to convert them. Washington Post photo by Annie Gowen

"This has never happened in West Bengal," Ramiz said. "Bengal is very beautiful - our society, our culture. This is the place of poets. We don't believe in this kind of thing."

Facebook took down Mylavarapu's threat page a few days after his Jan. 28 post caused an uproar on social media, but took longer to track and remove hundreds of duplicate versions posted by others.

"I don't think Facebook has a clue how to monitor hate speech," said Maya Mirchandani, a senior fellow who co-wrote the study. She said that more proactive text monitoring systems are not in place, including among its rapidly growing non-English speaking audiences.

"Maintaining a safe community for people to connect and share on Facebook is absolutely critical to us," a Facebook spokesman said in a statement. "We have policies that prohibit hate speech and credible threats of harm, and we will remove this content when we're made aware of it."

The Washington Post