EASTON, Pennsylvania -- A Lehigh University student has been arrested after authorities say he had been trying to kill his roommate for months.
Prosecutors announced Thursday that 22-year-old Yukai Yang will be charged with attempted homicide and related offenses.
It was inside his Lehigh University dorm where police say the student from China developed a murder plot, and carried it out trying to discreetly and slowly kill his roommate.
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Authorities say Yang, a chemistry major, sickened his roommate with thallium and possibly other chemicals last spring. Juwan Royal experienced symptoms that included dizziness, shaking and vomiting, and his blood tested positive for thallium.
"This was over a period of time with small amounts of poisoning occurring," said Northampton County District Attorney John Morganelli. "It was added to food and drinks in the refrigerator."
The DA says Yang poured it in his long time roommate Juwan Royal's milk and mouth wash.
"This victim is still experiencing physical symptoms from this poisoning that occurred," Morganelli said.
The first recorded incident happened back on March 18th when Royal called campus police to report: "He was sitting at his computer before feeling dizzy and passing out."
Then on March 29th he called for help again, telling officers: "He had been throwing up for over 45 minutes and felt very shaky."
Then shortly after that someone damaged and defaced Royal's property.
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The report states on April 5th there was: "Damage to the victim's television and damage was also done to the victim's bed and desk where the phrase 'N*****, get out of here' was written in black marker."
A day after the property damage, Yang was arrested.
Authorities say he submitted a written statement that matched the handwriting on Royal's desk. Plus, he was the only one who had access to the room.
After his arrest, investigators were able to confiscate his cellphone and computer. It was information found on those devices that helped police determine that Royal needed a blood test.
Thallium was found in his system.
According to the district attorney, Yang "admitted to purchasing various chemicals on the internet, including thallium, and stated they were purchased with the intent to harm himself if he did poorly on future exams."
The district attorney wasn't buying his story.
Yang faces many charges, including attempted homicide and ethnic intimidation.
As for Yang's roommate, Juwan Royal, we are told he is still experiencing side effects from the chemical while trying to make a recovery.
Chemistry major accused of poisoning roommate's food, milk, mouthwash