Errson boarded a plane in Gothenburg, Sweden, Tuesday bound for Istanbul with a 52-year-old Afghan man on board who was being deported to Kabul.
The young Swedish activist, reportedly a ticketed passenger, started live-streaming herself protesting the deportation and that video has racked up more than 2.5 million views and counting.
As she walked through the aisles, she explained that "he will most likely get killed" in Afghanistan. She started tearing up, as some people applauded and others heckled her.
“What is more important, a life, or your time? … I want him to get off the plane because he is not safe in Afghanistan," she said. "I am trying to change my country’s rules, I don’t like them. It is not right to send people to hell.”
At one point, a man grabbed her phone and told her to stop filming.
Ersson repeatedly interacted with the head flight attendant, telling him: “I am doing what I can to save a person’s life. As long as a person is standing up, the pilot cannot take off. All I want to do is stop the deportation and then I will comply with the rules here. This is all perfectly legal and I have not committed a crime.”
She stood until the man was removed from the flight, responding to questions she posted on Facebook: "The deportation was interrupted. I don't know any more than that, shutting off my cell phone now."
In a separate Facebook post, she wrote, "From now on, if you as a reporter want information contact Sittstrejken I Göteborg," an organization that has not responded to ABC News' request for comment.
In the past two years, European countries have deported more than 13,000 Afghans to Kabul, according to Amnesty International and the European Union, arguing the country is safe now.
The United Nations disagrees. In the fourth quarter of last year, about 100 people were killed every single day in Afghanistan, according to the U.N.
And the U.N. said last week that 1,692 civilians were killed in the first six months of 2018, more than at any comparable period of time since records began being compiled a decade ago.
Over that same period of time, 3,430 people were also injured.
“Given the numbers of people who continue to be killed and injured in Afghanistan, it is unconscionable to claim that the country is safe enough to send people back to," Omar Waraich, deputy director for South Asia at Amnesty International, said.
"Callously diverting their eyes from the bloodshed, states that once pledged their support for the Afghan people are now putting their lives in immediate danger, in brazen violation of international law,” Waraich added.
“The international community cannot abandon Afghans fleeing conflict and violence at this time."