Chan Tong-kai (陳同佳; 1998 -) was responsible for murdering his girlfriend while they were in Taiwan and fleeing back to Hong Kong after the murder.
He was only sentenced for money laundering in Hong Kong and not murder, due to the murder happening in Taiwan. Chan could not be extradited to Taiwan either since there is no extradition treaty between Hong Kong and Taiwan, which sparked the beginning of the controversial Hong Kong extradition bill.
Chan and his girlfriend Poon Hiu-wing (潘曉穎) met in July 2017 while working in the same company, and went to Taiwan together in February 2018.
During their trip in Taiwan, Poon confessed that she was pregnant from her ex-boyfriend and showed Chan films of her having sex with other men. Out of rage, Chan smashed her head against the hotel walls and strangled her until she died. He then packed the corpse into a suitcase and went to bed.
On the next morning, Chan disposed all of Poon's belongings except her credit card, iPhone and digital camera. He dragged the suitcase with Poon's body inside and disposed the body near Tamsui River.
After Chan went back to Hong Kong, he spent HKD19,200 (aprox. USD2,500) with Poon's credit card.
Poon's parents reported her missing on March 5, 2018. They also found Chan's departure and arrival records from Taiwan. With this information, Poon's father immediately flew to Taiwan to file a missing person report and seeked help from the Taiwanese authority.
The Taiwanese police found footage from surveillance camereas showing Chan and Poon entering the hotel and only Chan leaving with a pink suitcase. Taiwan's Criminal Investigation Bureau contacted counterparts in Hong Kong and summoned Chan for questioning. Chan confessed to killing his girlfriend and revealed where he disposed of the body and was arrested by the Hong Kong police.
The Hong Kong police could not prosecute him on murder or manslaughter since they did not have jurisdiction over crimes committed outside Hong Kong, so Chan was charged with money laundering, and was sentenced to 29 months in prison.
The Taiwanese authorities sought to lay charges of murder and asked the Hong Kong government for mutual legal assistance three times but received no response.
Later in December 2018, Taiwan issued a warrant for Chan. The Hong Kong government proposed the controversial extradition bill which caused protests that lasted serval months.