Hong Kong recorded three more cases of the novel coronavirus pneumonia (NCP), bringing the total number to 29 as of Sunday, according to the government.

The newly confirmed cases include a 24-year-old man and his over-90-year-old grandma and a 70-year-old man, who has chronic disease.

The youth and his grandma had a gathering with another 17 family members on Jan 26 at a restaurant in Kwun Tong, said Chuang Shuk-kwan, head of the Communicable Disease Branch of the Centre for Health Protection of the Department of Health.

Besides the confirmed cases, nine out of the 17 family members had felt under the weather. Seven were found positive in initial NCP test while two were waiting for the initial test results.

Another two of the 17 family members are from mainland. One of them stayed in Hong Kong from Jan 24 to 28 while the other one from Jan 24 to 29. They are both in mainland now, with one's lung scan showing no infection and the other one waiting for test results.

Chuang said the source of infection was unknown.

She called on residents to cut off family gatherings in order to stop spread of the virus.

The restaurant in Kwun Tong announced it would close for checks after the new cases.