A Harvard Medical School scientist from Russia who had been detained since February for bringing frog embryos into the country for research purposes was released Thursday after prosecutors withdrew their request to hold her without bail while a criminal case against her is pending.
Kseniia Petrova, 30, wearing a “Hakuna Matata” T-shirt, erupted in laughter as she was greeted in the hallway at the federal courthouse in Boston by friends and colleagues from the Harvard laboratory where she worked, saying, “This is amazing.”
Minutes later, as she stood alongside her immigration and criminal defense lawyers outside the courthouse, she said, “I just want to thank everyone for supporting me,” especially those who had written letters, called, and visited during her nearly four months in custody.
While she remains free, with conditions that her travel be restricted to New England, Petrova still faces the federal smuggling charge and is opposing the government’s efforts to deport her to Russia, a country she fled in 2022 and where she says she fears she will be arrested for protesting Russia’s war against Ukraine.
Petrova’s immigration lawyer, Gregory Romanovsky, said she is not a danger to the community or a flight risk and it was hard to explain why she had been jailed for so long. “Her legal claim is very strong,” he said, adding that it was unclear what she will do once the cases are resolved.
“She has not decided whether she wants to stay in the United States,” Romanovsky said. “She has offers from different countries around the world, countries that are eager to support the important research that she’s doing. She’s weighing her options at the moment.”
Petrova’s case drew national attention after she was detained at Logan International Airport on Feb. 16 for failing to declare frog embryos and embryo slides that she was carrying in her luggage. At the time, she was returning from a two-week vacation in France and transporting the samples back to the Harvard lab, where she was involved in research on aging and disease.
Upon her detention, US Customs and Border Protection immediately canceled her visa and began deportation proceedings. She was moved to a detention facility in Louisiana that same day. Her lawyers have argued that the samples were harmless, and that, historically, such infractions have been considered minor and punishable with a fine. They have accused the government of detaining her in violation of her due process rights.
The case against her was sharply escalated in May when the US attorney’s office charged her with a federal crime of attempting to smuggle the frog embryos into the United States.
During Thursday’s hearing, Petrova was handcuffed and wearing a jail-issued orange suit as she was escorted into the courtroom by deputy US marshals.
US Magistrate Judge Judith Dein asked her stand, then said, “I know you’ve had a hearing already in Louisiana. Welcome to Massachusetts.”
Prior to the hearing, prosecutors had notified the court that they were seeking to detain Petrova without bail while the criminal case was pending.
However, Assistant US Attorney Nadine Pellegrini told the judge that prosecutors and the defense agreed that Petrova should be released on personal recognizance and ordered not to travel outside of New England. Pellegrini also assured the judge that immigration officials would not attempt to take Petrova into custody once she was released.
Dein ordered Petrova’s release and a short time later she was free. The judge scheduled a hearing in the case for Wednesday..
Prosecutors allege that text messages found on Petrova’s phone after she was stopped at the airport revealed that she was aware that she was required to report the biological samples. They allege a colleague asked her how she planned to get them through customs and she replied, “No plan yet. I won’t be able to swallow them.”
However, Petrova’s lawyers argued that no charges were warranted.
A graduate of a renowned Russian physics and technology institute, Petrova was part of a team investigating how to extend the human life span by studying the way cells rejuvenate. She was also involved in research for cancer, heart disease, diabetes, and other chronic ailments.
Prior to her return from France, Petrova’s supervisor at the Harvard laboratory asked her to bring samples of frog embryos from the Institut Curie, a cancer research center in Paris, according to a court filing by her lawyers. “The samples were non-hazardous, noninfectious, and non-toxic, intended solely for fundamental research purposes,” they wrote.
Shelley Murphy can be reached at shelley.murphy@globe.com. Follow her @shelleymurph.