Experts investigate near the site of a deadly blast in central Bangkok, Thailand, August 18, 2015. [Photo/Agencies]

As of 7 p.m. local time on Tuesday, six Chinese nationals, including four from the mainland and two from the Hong Kong Special Administrative Region, had been confirmed dead in a Bangkok explosion Monday night, the Chinese Embassy in Thailand said Tuesday.

Another 22 Chinese, including 17 from Chinese mainland, two from Hong Kong and three from China's Taiwan are under treatment in hospital, the embassy said, adding more than 10 others, who sustained minor injuries, have been discharged from hospitals.

There is one Chinese who remains missing, according to the embassy.

China on Tuesday urged Thai authorities to fully investigate the blast and to severely punish the perpetrators, Chinese Foreign Ministry spokeswoman Hua Chunying said in a statement posted on its website.

The two Hong Kong people who died were women aged 19 and 24. Hong Kong Immigration department also confirmed six other Hong Kong residents injured in the incident and they have been sent to local hospitals for treatment.

Three Hong Kong immigration officers will fly to Bangkok this morning to provide help to the victims and their family members.

The Immigration Department advised residents already there to attend to personal safety and remain at safe areas.