Former Beth Israel researcher admits he lied to Logan customs agents about all the vials filled with brown liquid wrapped in a sock in his luggage

Zaosong Zheng, 31, pleaded guilty yesterday to one count of making false, fictitious or fraudulent statements when he was caught at Logan Airport trying to smuggle 21 vials full of cells he hoped to use for research to publish a paper after he got back to his native China, the US Attorney's office reports.

Zheng had been in Boston as a research fellow doing cancer research at Beth Israel Deaconess Medical Center, when he set off to Logan on Dec. 9, 2019 for a trip home to Guangzhou, China, where he was a doctoral student at Sun Yat-sen University with a focus on bladder and renal cancer,

Zheng's lawyers had argued he simply made a mistake not declaring the test tubes, but prosecutors said researchers who bring biologic samples with them on overseas trips for legitimate reasons don't put them in a sock hidden in a checked bag.

According to an affidavit by an FBI agent on the case, Zheng at first repeatedly denied any carrying any "biological items or research material in either his carry-on or checked luggage" when questioned by customs agents at the airport.

But then, the affidavit continued, Zheng admitted he had the vials in one of his bags, but said he was transporting them for a friend, before finally telling investigators he had filled the vials with samples from cell lines used by Beth Israel researcher Zhang Tao, in whose lab he worked, and that he planned to use the samples to conduct his own research in China and then publish a paper under his own name.

After Zheng's arrest, at least one Boston hospital sent a memo to its researchers reminding them to declare any samples they were bringing with them.

Zheng was one of at least 18 people stopped at Logan with improperly or undeclared biological samples - although his case was the only one publicized by the US Attorney's office, along with two other completely unrelated arrests of people with ties to China.

He now faces sentencing on Jan. 6. Although his punishment will be determined by US District Court Judge Denise Casper, he has agreed to an order to ship him out of the country after the hearing, the US Attorney's office reports.