Shortly after arriving at an airport in Minneapolis on Wednesday, Yassmin Abdel-Magied, one of Australia’s most prominent feminist Muslim activists, said border agents detained her, confiscated her Australian passport, then put her on a flight leaving the U.S.

Abdel-Magied was in the U.S. to give speeches at the PEN America World Voices Festival in New York next week. The title of one of her presentations was fitting for her rejection: “The M Word: No Country for Young Muslim Women.”

Abdel-Magied, who is also an author and engineer, founded the advocacy group Youth Without Borders.

In a series of tweets, Abdel-Magied said U.S. immigration officials at the airport in Minneapolis took away her phone, canceled her visa and denied her entry into the country shortly after she arrived.

The border security agent, whom Abdel-Magied said was named “Officer Herberg,” assessed the Muslim activist’s situation and told her, “We’re sending you back!”

Abdel-Magied said she was in Minneapolis for only three hours before Customs and Border Patrol put her on a flight out of the country.

New York Times reporter Isabella Kwai, who spoke to Abdel-Magied before her departure from Minneapolis, said that the border agents denied the activist entry into the U.S. because the “B1/B2 visitor visa” she was issued “was the wrong visa for speakers, although she’s entered on it before to speak at events.”

In a statement released Thursday, Abdel-Magied said that she had returned to London, where she lives, after the “validity” of her visa to enter the U.S. was “challenged.”

“I have previously travelled to the United States on the visa that I sought entry with this on occasion,” she said. “I am now seeking advice and working to resolve this issue as soon as possible. I appreciate the interest and concern and look forward to future travels to the United States.”

A B-1 visitor visa allows foreign citizens to travel to the U.S. to attend a scientific, educational, professional or business convention or conference, according to the State Department’s Consular Bureau. People traveling with this visa cannot use it to participate in “paid performances, or any professional performance before a paying audience.”

A spokesperson for Customs and Border Patrol confirmed to HuffPost that Abdel-Magied was denied entry because she “did not possess the appropriate visa to receive monetary compensation for the speaking engagements she had planned during her visit to the United States.”

“She was deemed inadmissible to enter the United States for her visit, but was allowed to withdraw her application for admission,” the spokesperson said in a statement, adding that Abdel-Magied is “eligible to reapply for a visa for future visits.”

The official also said that the “issuance of a visa or a visa waiver does not guarantee entry to the United States.”

PEN World Voices Festival organizers defended Abdel-Magied’s visa in a statement forwarded to HuffPost, arguing that the activist was “traveling on a type of visa that she had used in the past for similar trips without issue.”

Festival organizers called on Customs and Border Patrol to allow her back into the U.S. They did not immediately respond to HuffPost’s inquiry on whether Abdel-Magied was being paid for her appearance at the festival.

“Plane is up,” Abdel-Magied wrote in one of her last tweets Wednesday evening. “See y’all on the other side, inshallah.”

The final destination of Abdel-Magied’s return flight was unclear, and she did not return HuffPost’s request for comment late Wednesday.

Abdel-Magied, a 2015 recipient of Queensland’s Australian of the Year award, is no stranger to the controversy that comes with being a feminist, activist and Muslim woman ― especially one who is vocal about social justice.

Her liberal views, her challenging of capitalism and her defense of Islam have led some Australian politicians, and many more online trolls, to publicly denounce her.

In February 2017, a conversation on immigration issues between Abdel-Magied and Australian Sen. Jacqui Lambie turned into a yelling match on the Australian Broadcasting Corp.’s political show “Q&A.”

During the exchange, Abdel-Magied called Islam “the most feminist religion.”

“My frustration is that people talk about Islam without knowing anything about it, and they’re willing to completely negate any of my rights as a human being,” she told Lambie.

That exchange, which went viral across the country, was one incident that led her to become “the most publicly hated Muslim in Australia,” Abdel-Magied later wrote in an op-ed for The Guardian.

Then came a controversial Facebook post she wrote on Anzac Day, a memorial day in Australia honoring military service members.

“Lest we forget (Manus, Nauru, Syria, Palestine),” she wrote on the April 25 holiday, recalling victims of war in other countries, including war refugees.

The post, which she later deleted and apologized for, evoked outrage across Australia, with many accusing the activist of being insensitive.

In July 2017, three months after her Anzac post and five months after her exchange with Lambie, Abdel-Magied left Australia and moved to London.

“Just last year, Yassmin Abdel-Magied was hounded out of Australia by ferocious media and online attacks,” reads a blurb for her PEN World Voices Festival event.

She was scheduled to speak alongside Muslim American activist Amani Al-Khatahbeh about “how to survive and thrive in cultures that hate them.”

In a statement, festival organizers said, “We are dismayed that an invited guest to our annual PEN World Voices Festival in New York … was turned away by US Immigration officials in Minneapolis, reportedly had her phone and passport seized, and was put back on a plane to Amsterdam.”

“Abdel-Magied is an advocate of the rights of Muslim women and refugees and is a citizen of Australia, traveling on that country’s passport,” the statement continued.

“The very purpose of the PEN World Voices Festival, founded after 9/11 to sustain the connectedness between the U.S. and the wider world, is in jeopardy at a time when efforts at visa bans and tightened immigration restrictions threaten to choke off vital channels of dialogue that are protected under the First Amendment right to receive and impart information through in-person cultural exchange.”