Chinese citizens in Afghanistan should be on high alert after three Chinese were found dead in an apartment on Thursday, China's embassy in Afghan said on Sunday.

The three victims were among five Chinese targeted last week, one of whom is still missing, while another managed to escape a kidnap attempt and raise the alarm. The search for the missing person is still underway, the embassy told China Daily.

The Chinese embassy also urged Afghan authorities to arrest the killers as soon as possible and secure the safety of Chinese institutions and citizens in the country.

It was not immediately clear whether the five Chinese victims were all related and the attacks coordinated.

The man who survived a kidnap attempt said he was forced into a car driven by a local man on Friday morning but managed to jump out of the vehicle as it left Kabul. He called a nearby US military base for help and was later returned to the Chinese embassy.

The embassy declined to release the man's identity while the search was ongoing for the missing victim. The embassy is working closely with the local police to find him, and he has not been pronounced dead because no body has been found, according to the embassy's councilor, Pang Chunxue.

With no suspects arrested, it is still unclear if the Chinese nationals were purposefully targeted, the embassy said. An Afghan was also found dead in the apartment along with the three dead Chinese citizens.

The apartment was on the second floor of a building in central Kabul. Alcoholic beverages were found in the room, police said.

Photos of the crime scene show little furniture, apart from a messy bed. Clothing and power cables were found on the floor, Xinhua News Agency reported.

The attack was committed during Eid al-Fitr, an important religious holiday celebrated by Muslims. The manager of the apartment said the victims were likely having a party before the attack, according to Xinhua.

China Daily-Reuters-Xinhua