EASTON — A former Lehigh University student on Monday admitted poisoning his roommate’s food and drink with a heavy metal substance.

Yukai Yang, 24, pleaded guilty to attempted murder. Under the terms of a plea agreement, the Northampton County District Attorney’s Office will withdraw other charges in two separate cases against Yang.

Yang admitted he purchased thallium in March 2018 and the chemistry major acknowledged he began giving it to his roommate, Juwan Royal. Royal testified in an earlier court hearing that he suffered weight loss, headaches and nausea.

The roommate was diagnosed with heavy metal poisoning in April 2018.

Yang faces between six to 20 years in state prison when he’s sentenced on Jan. 21.

Yang is not a U.S. citizen, and the judge told him he will likely face deportation.

Yang’s student visa had been revoked after his arrest.