The Department of Homeland Security at the last minute has decided to bar a young Syrian cinematographer from entering the U.S. to attend The Oscars Sunday. The civil-war documentary he risked his life to work on has been nominated for an award.

Khaled Khatib, 21, had obtained a visa and was due to fly to Los Angeles via Istanbul Saturday. But U.S. officials suddenly said they’d found unspecified “derogatory information” linked to Khatib, The Associated Press reported Saturday. Khatib was detained in Turkey, and he now needs a passport waiver to enter the U.S., which he will not be able to obtain, according to internal Trump administration documents seen by the AP. “Derogatory information” is a broad category that can be something serious to passport irregularities. It’s not clear why Khatib was detained in Turkey.

Khatib was a cinematographer on the 40-minute Netflix documentary “White Helmets,” which has been nominated for Best Documentary, Short Subject. It follows rescue workers for the Syrian Civil Defense White Helmets, who have saved tens of thousands of lives during the nation’s bloody civil war. The group was founded in 2012 after a Syrian Air Force attack on civilians. It was nominated for a Nobel Peace Prize in 2016. Khatib, who started filming the workers when he was just 16, is also a volunteer with the group.

Some 120 White Helmets have been killed in recent years, including Khaled Omar, known as the “miracle baby rescuer” in Aleppo, after pulling an infant out alive from the rubble of the baby’s home in 2014. Omar was killed in an airstrike in 2016.

“White Helmets” director Orlando von Einsiedel had made a plea to the U.S. to allow those who had worked on and been featured in the film to attend the Oscars. The experience would not only be rewarding for them, he said, but with the world “so divided we could all learn from the White Helmets’ message od compassion and dignity.” After a court halted President Donald Trump’s travel ban, the filmmakers revived plans to bring Khatib and White Helmets leader Raed Saleh to Los Angeles.

Saleh will also not be attending now because of the demand of work in Syria.

Regretfully we won't be at the OSCARS due to intensity of work, our priority continues to be helping civilians & rescue operations in #Syria — Raed Al Saleh (@RaedAlSaleh3) February 24, 2017

Iranian filmmaker Asghar Farhadi, whose movie “The Salesman” is up for Best Foreign Language Film, said last month that he would not attend the awards ceremony because of Trump’s controversial ban.

But Farhadi and the directors of the other four movies in the foreign language category issued an angry statement on Friday blasting America’s “climate of fanaticism and nationalism.” It’s unlikely the directors yet had word that Khatib would not be allowed to attend the Oscars.

“The fear generated by dividing us into genders, colors, religions and sexualities as a means to justify violence destroys the things that we depend on — not only as artists but as humans: the diversity of cultures, the chance to be enriched by something seemingly ‘foreign’ and the belief that human encounters can change us for the better,” their statement reads

“These divisive walls prevent people from experiencing something simple but fundamental: from discovering that we are all not so different.”

Regardless of “who wins the Academy Award for Best Foreign Language Film on Sunday, we refuse to think in terms of borders,” they wrote. “We believe there is no best country, best gender, best religion or best color. We want this award to stand as a symbol of the unity between nations and the freedom of the arts. Human rights are not something you have to apply for. They simply exist — for everybody.”

Khatib was looking forward to traveling to the Oscars. “If we win this award, it will show people across Syria that people around the world support them,” he said when he announced his plans to attend this month. “It will give courage to every volunteer who wakes up every morning to run towards bombs.”

“If I cannot enter the U.S., I will not give up,” he added. “We know that we have many friends in the U.S., that there are people that share our humanitarian values. I look forward to meeting them all one day.”