At the Women’s March on Washington DC on Saturday, almost constantly within sight was a poster of a Muslim woman wearing the American flag as a hijab.

Just days after the massive protest, however, a Palestinian American woman who co-organised the march is facing Islamophobic backlash.

Despite the appeal of the demonstration and similar marches across the country, which have been described as the largest protest movement in US history, Linda Sarsour is facing attacks by internet users and fake news websites, including false accusations of ties to terrorism.

But her supporters, even some of her political opponents, are voicing solidarity with Sarsour on social media, to counter the campaign against her.

The posts against Sarsour, which included assaults on her character, were featured in many right-wing websites, including popular outlets like the Daily Caller.

The seemingly orchestrated effort centred on falsehoods, Islamophobic and misogynistic slurs.

Headlines included: "DC Women’s March Organizer Is Pro Sharia Law and Found To Have Ties To Terrorists Organization"; "The Anti-Semite Who Organized The Women’s March On Washington"; "Terrorist-tied co-chairman of Women’s March relies on the stupidity of liberal American females to push sharia"; "Women’s March Organizer Recently Met Ex-Hamas Operative, Has Family Ties To Terror Group".

The counter campaign

On Monday, the hashtag #IMarchWithLinda was trending on Facebook. Supporters, major rights groups and even politicians used it to defend Sarsour from the defamation attempts.

#IMarchWithLinda @lsarsour because she marched for all of us. I march with Linda because we are bound in each others liberation. 👊👊👊 — Fred (@WaywardWinifred) January 23, 2017

Hundreds of social media users denounced the negative focus on Sarsour as Islamophobic and praised her character.

Amnesty International tweeted that Sarsour “embodies the spirit of a true activist,” urging followers to not let fear win.

Not this time, trolls. I stand with the incredible and inspiring @lsarsour. In defiance. Indivisible. #IMarchWithLinda — Naomi Klein (@NaomiAKlein) January 23, 2017

Imraan Siddiqi, a writer and activist, compared the attacks on Sarsour to the campaign against Muslim US congressman Keith Ellison - a "snippet of what it's like to be Muslim in public life".

"If they're coming for Linda Sarsour, they're coming at all of us. We got u sis," Khaled Beydoun, a law professor at the University of Detroit Mercy, wrote on Facebook.

The Southern Poverty Law Center said it stands with Sarsour against all forms of hate and bigotry.

#IMarchWithLinda because @lsarsour is changing the narrative of what it means to be a American Muslim woman. She is #MuslimWomenRising pic.twitter.com/EPIvnYQQg7 — MuslimWomensAlliance (@MWAChicago) January 23, 2017

'Unapologetically Muslim American'

Sarsour, one of the most prominent US Muslim activists, has successfully campaigned to get New York City public schools to close on Muslim holidays.

The community organiser, known as the “Brooklyn Hijabi,” also served as a surrogate for Bernie Sanders during the Democratic presidential primaries last year.

Thank you @lsarsour for helping to organize the march and build a progressive movement. When we stand together, we win. #IMarchwithLinda — Bernie Sanders (@BernieSanders) January 24, 2017

At the Women’s March, Sarsour called herself “unapologetically Muslim American”.

She said she will respect the presidency, but not US President Donald Trump.

"I will not accept an administration that won an election on the backs of Muslims and Black people and undocumented people and Mexicans and people with disabilities and on the backs of women," said Sarsour, who is also the executive director of the Arab-American Association of New York.

She also said the "character assassination attempts" are about her identity.

"I need extra prayers sisters and brothers. The opposition cannot fathom to see a Palestinian Muslim American woman that resonates with the masses," she wrote on Facebook on Monday. "Someone whose track record is clear and has always stood up for the most marginalized."

She added that the "coordinated attack campaign" against her is not unprecedented, but has been more intense this time.

"They will not succeed," she continued in the Facebook status. "I have helped build a movement, I am ready for what's to come so they can spew alternative facts and piece a twisted narrative together if they want - I and we will still rise."

Sarsour added that right-wing activists are scared because while they have always been outnumbered, on the weekend they were also out-organised.

NY Daily News columnist Shaun King described Sarsour as "one of the most effective, skilled, passionate organisers in the world".

New York State Senator Gustavo Rivera condemned “online trolls” attacking Sarsour.

"Let's join forces and let these trolls know, loud and clear, that we have her back," he called on his followers on Facebook.