By Nate Raymond

BOSTON, Nov 3 (Reuters) - US prosecutors moved on Tuesday to drop criminal charges against a Russian-born scientist at Harvard University accused of smuggling frog embryos into the United States after she argued the Trump administration had singled her out for prosecution.

Federal prosecutors in Boston said in a court filing they were dismissing the charges against Kseniia Petrova after a federal judge cleared the way for her to obtain evidence supporting her claim that she was being vindictively prosecuted.

Prosecutors in the filing said that while they viewed those claims as "meritless," continuing to prosecute the case after the judge's order "would divert significant time and attention from more substantial federal interests."

A lawyer for Petrova had no immediate comment.

The biomedical researcher had been taken into custody by US immigration authorities at the airport in Boston in February 2025 after her visa was revoked upon her return from a trip to France.

Prosecutors brought a criminal case against Petrova, who worked at Harvard Medical School, in May 2025 as a federal judge in Vermont weighed ordering her release from the immigration detention facility in Louisiana.

Petrova, who was ultimately released on bail in June 2025, pleaded not guilty to the smuggling and false statement charges she faced. She has said her boss asked her to bring back frog embryo samples for experiments.

Her lawyers argued the charges were brought in retaliation for her decision to challenge the immigration proceedings against her and said that the case had been brought amid a broader campaign by President Donald Trump's administration against researchers, universities and Harvard itself.

In April, a federal judge in Vermont ruled that Petrova's visa had been unlawfully canceled. And last month, a judge in Boston concluded she put forward sufficient evidence that she was selectively prosecuted to entitle her to obtain access to government records to support her claim.