Ambassador Anna Lindstedt returned to Stockholm on Wednesday to meet with officials from the foreign affairs ministry, the Swedish Embassy in Beijing said by phone. Lindstedt is not under criminal investigation.
The ministry later confirmed that Lindstedt's departure was related to meetings she arranged between Angela Gui, the daughter of detained Swedish book publisher Gui Minhai, and the two businessmen.
"The ambassador has acted incorrectly in the sense that the foreign ministry had no knowledge that the meetings took place," spokeswoman Catherine Johnsson told The Associated Press. She said the internal investigation was aimed at getting "an overall picture of what has happened," and that "as far as the action of the ambassador is concerned, we must wait for what the inquiry will come up with."
Angela Gui published an account Wednesday in which she described the meetings as "strange." She wrote on Medium, an online publishing platform, that the businessmen threatened her after initially offering to help secure her father's release from prison in China.
Gui Minhai, a naturalized Swedish citizen, co-owned a Hong Kong store which sold gossipy books about Chinese leaders.
Gui, 53, went missing in 2015 from his seaside home in Thailand, turning up months later on Chinese television saying he had turned himself in for an alleged 2003 drunken driving accident in which a female college student was killed.
Several of Gui's colleagues from his Hong Kong publishing house also went missing in quick succession, sparking suspicions that mainland security forces were seeking to snuff out independent voices in the semi-autonomous city.
Gui was released in October after completing a two-year sentence, but committed to remaining in Ningbo, where he was born, until an investigation was completed into charges of running a business illegally.
In January 2018, he was taken off a train by Chinese police while in the presence of two Swedish diplomats with whom he was traveling to Beijing. Sweden said its officials were taking him to seek medical treatment. China said Gui was being investigated for leaking state secrets.
Gui later told pro-Beijing media outlets that he never wished to leave China and that Sweden was using his case to "create trouble" for China's government. The statement from Gui, who spoke in a detention facility flanked by police, was immediately denounced by rights activists as coerced.
Angela Gui is a Ph.D. candidate at the University of Cambridge who has become a self-described "accidental activist" for her father. She wrote in her Wednesday post that the role has landed her in a "fair number of bizarre situations," but few of the same magnitude as her encounter with Lindstedt and the businessmen.
She said Lindstedt convinced her to fly to Stockholm on Jan. 24 to explore a "new approach" to her father's case. During a two-day meeting with the businessmen and Lindstedt, she said, the businessmen told her they could arrange a Chinese visa and job for her and that they had connections within China's ruling Communist Party.
They then told her they had already started to negotiate over her father's case without her prior knowledge, according to Angela Gui. One businessman said it was possible that Gui Minhai would be released, but only if Angela Gui promised to stop publicizing her father's case for a month.
Gui wrote that one of the men told her, "You have to trust me, or you will never see your father again."
She later learned that no one at the Swedish foreign ministry had been informed of the meeting.
"I'm not going to be quiet in exchange for a visa and an arbitrary promise that my father 'might' be released," she wrote. "Threats, verbal abuse, bribes, or flattery won't change that."
In Sweden, Jonas Sjostedt, a lawmaker for the pro-government Left Party, accused the ambassador of "trying to silence the daughter of a Swede who is a political prisoner in China."
"Someone who is representing Sweden has instead been running errands for a foreign power," he said Wednesday on Swedish broadcaster SVT TV.
Sweden announced last month — prior to the incident described by Gui — that Lindstedt was leaving the Beijing post to become ambassador to the U.N. 2030 Agenda for Sustainable Development. She was to start in the new position in March.
Sweden's relations with China were also roiled last year by Beijing's demands for punishment, compensation and an apology over an incident in which Swedish police removed an elderly couple and their son from a hotel on Sept. 2 after they arrived a day before their booking and refused the staff's requests to leave.
Associated Press writer Jan M. Olsen in Copenhagen, Denmark, contributed to this report.