Hong Kong's Center for Health Protection (CHP) reported 14 additional confirmed cases of COVID-19 on Thursday, taking the total tally to 11,718.
There were 12 imported cases and two untraceable local cases, Principal Medical and Health Officer of CHP's Communicable Disease Branch Albert Au said at a press briefing.
Of the imported cases, four were infected with the N501Y mutant strain. A total of 235 infections with the N501Y mutant strain have been found in Hong Kong so far, according to the CHP.
Au said that there were also 30 preliminary positive cases, of which 21 were local infections. The samples of all these cases were from the same laboratory.
It was unusual that a large number of preliminary positive cases were reported in the same laboratory, and some of these cases were tested negative in the public hospital, Au said, adding that the CHP has invited an infectious diseases expert from the University of Hong Kong to inspect the laboratory.
Hong Kong launched a COVID-19 vaccination drive on Feb. 26. About 773,900 people have received the first dose of vaccine, and about 399,200 have received the second so far.