A passenger service staff member at Singapore's international airport is one of the two vaccinated cases who have tested "preliminarily positive" for the new Omicron variant of the coronavirus, the health ministry has said.

The local case is a 24-year-old Singaporean woman who worked in the transit holding areas of Changi Airport Terminal 1 and 3 where she might have interacted with transit passengers from Omicron-affected countries, said the Ministry of Health (MOH) on Thursday.

"Given its high transmissibility and spread to many parts of the world, we should expect to find more Omicron cases at our borders and also within our community," Channel News Asia cited the ministry as saying.

If confirmed, the woman, on whom various tests are being carried out, would be Singapore's first local Omicron case, according to the report.

The other case that tested "preliminarily positive" for the variant is a 46-year-old woman who returned to Singapore via a Vaccinated Travel Lane (VTL) from Germany on December 6 on Singapore Airlines flight SQ325.

Her pre-departure test in France on December 4 was negative for Covid-19 infection. Upon arrival in Singapore, her PCR test on December 6 returned negative. She then developed a runny nose a day later and sought medical treatment on Wednesday.

The woman tested positive for Covid-19 infection on the same day and was confirmed to have the S-gene Target Failure on Thursday, the ministry said.

Singapore Covid cases

Singapore reported 682 new Covid-19 cases and five deaths on Thursday. They were 649 new cases in the community (local), 16 from dormitories for migrant workers and 17 who arrived here from abroad.

The total number of Covid-19 cases in Singapore now stands at 271,979 and coronavirus-related deaths at 779 since the pandemic began.

The Attorney-General Chambers (AGC) prosecuted 1,020 people and business entities between April 2020 and October 2021 for breach of regulations under the Covid-19 (Temporary Measures) Act, and Covid-19 (Temporary Measures)(Control Order) Regulations 2020, according to the Channel report.

Seven people were also prosecuted for Covid-19 government grants fraud.

The deputy public prosecutors who deal with Covid-19 cases work closely with the multi-ministry task force and agencies like the Ministry of Health, the police and Immigration and Checkpoints Authority to ensure that prosecution policies keep pace with the changes in Covid-19 regulations and prevailing national priorities to safeguard public health, said deputy public prosecutor Nicholas Lim.

"Prosecution of Covid-19-related offences is necessary as we need to send a strong message that public health measures must be taken seriously to control the transmission of the virus in the community, and that abuse of the support schemes will not be tolerated,” said Lim.

"These are trying times and we appreciate that the various Covid-19 regulations may be restrictive. However, we all need to play our part to ensure Singapore emerges stronger from this pandemic,” Lim added.

The first case of the virus emerged in Singapore in January 2020.