A Chinese college student has been charged with attempted murder after allegedly trying to slowly kill his roommate with rat poison.
Lehigh University student Yukai Yang, 22, is accused of lacing Juwan Royal's food, drinks and mouthwash with thallium over time, as well as vandalising the victim's belongings with racist graffiti.
He was charged on Thursday with attempted homicide and related offences, in addition to his previous charge of racial intimidation.
Royal's symptoms included dizziness, shaking and vomiting. He first called the police in February when he drank from a water bottle in his room and his tongue began to burn.
He woke his roommate up to tell him what happened and washed his mouth out, but his tongue reportedly remained sore for a few days following the incident.
On March 18, he notified police on the Bethlehem, Pennsylvania, campus when he fell ill again, with his flatmate allegedly telling officers that the milk in the fridge, as well as Royal's mouthwash had changed colour and he believed someone was tampering with his belongings.
"This was over a period of time with thallium being added to foods and drinks in the refrigerator," Northampton County District Attorney John Morganelli said Thursday morning. "He was getting worse all the time."
On the morning of March 29, Royal was taken to the hospital for treatment when he began throwing up and shaking.
About a week later, the words "n****r get out of here" were scrawled on his bed in graffiti.
When police compared the markings with Yang's handwriting, they noted similarities, and shortly after, blood tests found Royal had thallium in his system, a toxic metal that is colourless, odourless and tasteless.
Thallium, an ingredient formerly used in rat poison and banned in the US since the 1970s, can be fatal if consumed; Royal had 3.6micrograms per litre above the safe toxicity level for people.
After Yang's computer was seized, he confessed he had bought chemicals online, but insisted he had intended to use them on himself if his university grades started to slip.
He admitted to mixing the chemicals with food and drinks in the dorm refrigerator.
Royal is said to be "dumbfounded" by the allegations, believing that he had a good relationship with his roommate.
"Initially, Mr. Royal was dumbfounded by this as everyone else, because he believed they had a fairly cordial relationship as roommates," Assistant District Attorney Abe Kassis stated.
Yang has been sent to Northampton County Prison, in lieu of $200,000 bail. He is no longer enrolled at Lehigh University, and his student visa has been revoked.
"The Lehigh University Police Department has worked closely with the District Attorney's Office on the investigation and will continue to do so," a spokeswoman for the school told NBC News. "From the outset, our concern has been the health and safety of the victim of these alleged behaviours and, as such, Lehigh staff and faculty have been providing support, services and assistance."