Prosecutors are asking a federal court to keep a Chinese national behind bars after he allegedly admitted to stealing vials of scientific cancer research material from a Beth Israel lab and attempting to fly to China this month.

Zaosong Zheng, 29, a visa holder and employee at a Beth Israel Deaconess Medical Center research lab, was stopped at Logan Airport by federal agents on Dec. 9 for lying about transporting 21 vials of an unidentified biological substance on his luggage for a Beijing flight, an affidavit by an FBI agent stated.

Zheng allegedly admitted he stole the vials meant for cancer research from the lab and was planning to publish any discoveries as his own in China. After his release on a $100,000 secured bond on a charge of making a false statement, Zheng was kept in detention last week after U.S. District Court Pretrial Services found his bags packed during a home visit.

Also last week, the FBI interviewed Zheng’s ex-roommate who told them two other Chinese nationals recently smuggled biological materials to China, according to a recent motion by the government. The discovery led Assistant U.S. Attorney Benjamin Tolkoff to ask the court to reconsider Zheng as a serious flight risk.

“These facts … also strongly suggests that Zheng’s theft and attempt to smuggle biological specimens out of the U.S. was not an isolated incident,” Tolkoff wrote in the motion. “Rather, it appears to have been a coordinated crime, with likely involvement by the Chinese government.”

Beth Israel said in a statement, “Any efforts to compromise research undermine the hard work of our faculty and staff to advance patient care. We are grateful for the diligence and professionalism of federal law enforcement in this case and are fully cooperating with the government’s investigation of this matter.”

Beth Israel also told prosecutors it would fire any employee caught stealing and would revoke their J-1 Exchange Visitor’s Program visa.

Zheng’s alleged visa sponsor is Harvard University, according to court documents.

The government said it could file additional charges against Zheng, including theft of trade secrets and transportation of stolen goods in interstate or foreign commerce. A detention hearing for Zheng is scheduled for 11:30 a.m. Monday in federal court.