Monday's hostage crisis in Sydney, Australia may be over, but the circumstances surrounding the incident—in which three people, including the gunman, died and four others were injured following a 16-hour standoff—remain murky. Little is known about the motives of Man Monis, the suspect in the episode, or the details of the police operation that ended the crisis.

It was amid this prevailing uncertainty that a backlash against Australian Muslims started online. As reports spread quickly about the hostage situation—including the religious identity and nationality of the gunman, as well as the involvement of a black flag with the words of the shehada, the Muslim affirmation of faith, on it—the primary hashtag for the episode on Twitter, #SydneySiege, came to embody the occasional and predictable ugliness of the Internet. Xenophobic and anti-Muslim tweets went out and the Australian Defence League, an ultra-right-wing group, threatened confrontations in the Muslim-majority Sydney suburb of Lakemba.

Facebook

On a train, one passenger reportedly spotted a Muslim woman removing her hijab, ostensibly out of fear of being targeted. The passenger told her to put it back on and offered to walk with her in solidarity. And so began #IllRideWithYou. The hashtag went viral and is currently still trending worldwide, hours after the end of the hostage crisis.

That number is now fast approaching 250,000. The tweets included calls not to blame all Muslims for the hostage crisis and, more universally, for greater tolerance. The initiative also included offers of companionship and solidarity for Muslim travelers who might not want to travel alone. But despite the heartwarming subplot, the efforts to head off an anti-Muslim backlash in Australia come at a particularly heated moment in the country.

Australian government

Only months ago, the government released an incendiary video and poster for its Operation Sovereign Borders campaign, a program designed to dissuade asylum-seekers and illegal immigrants from entering the country. The program didn't explicitly single out Muslims or legal immigrants, but the new material debuted in the context of a spike in attacks against Muslims in Australia linked to fears over the rise of ISIS. In September, the country's terror alert rose as dozens of Australians reportedly decamped to join the Islamic State.

Islam, meanwhile, is one of the fastest-growing religions in the country. "Thanks to immigration," The Economist noted, "the number of Muslims in the country grew by two-thirds in the decade to 2011. Muslims now account for just over 2% of the country’s population of 23m, many of them in the outer suburbs of Sydney and Melbourne."

On Monday, Muslim leaders in Australia condemned the Sydney siege and urged calm. Tessa Kum, who was credited with turning #IllRideWithYou into a hashtag, echoed that sentiment:

It is hard to feel hope when you feel helpless. #illridewithyou is a small act, but might be important for someone one day. My thoughts are with those involved, who will be affected for so long to come, and those uninvolved, who are being blamed none the less.