Chinese chemistry student Yukai Yang accused of slowly poisoning black roommate Juwan Royal at Pennsylvania’s Lehigh University

A Chinese former student at Lehigh University in Pennsylvania was accused Thursday of poisoning his roommate.

Yukai Yang, a 22-year-old chemistry major, slowly sickened his roommate with thallium and possibly other chemicals, lacing his food and drinks over the course of several months last spring, prosecutors said.

Yang will be charged with attempted homicide, aggravated assault and other offences, according to Northampton County District Attorney John Morganelli, who called the allegations “weird and bizarre”.

Taiwanese student Sun An-tso to be deported from US over gun charge

Thallium is odourless and tasteless, and can be fatal in humans. The soft metal is used internationally in electronics manufacturing and for other purposes. It once was an ingredient in rat poison in the US, but has been banned for that use since the 1970s.

Yang’s roommate, Juwan Royal, experienced progressively worse symptoms that included dizziness, shaking and vomiting, and his blood tested positive for thallium. Royal, who has since graduated, continues to suffer symptoms, authorities said.

Yang was already facing an ethnic intimidation charge for allegedly scrawling racist graffiti in their dorm room. Royal is black.

Yang, an international student from China, is no longer enrolled at Lehigh, which is in Bethlehem, Pennsylvania, about 80 miles west of New York City, and his student visa has been revoked. His lawyer did not immediately return a phone message Thursday.

The students were roommates for several years, and Royal once believed they had a good relationship, according to Morganelli.