Singapore's health ministry said it is looking into an “unusual surge” in infections after the city-state reported 5,324 new cases of Covid-19 on Wednesday, the most since the beginning of the pandemic.

Singapore also recorded 10 new deaths from the disease on Wednesday, taking the toll to 349.

"The infection numbers are unusually high today, mostly due to many Covid-positive cases detected by the testing laboratories within a few hours in the afternoon," the ministry of health (MOH) said in a statement on Wednesday night.

"MOH is looking into this unusual surge in cases within a relatively short window, and closely monitoring the trends for the next few days."

Singapore extended some of its social curbs last week to contain the spread of Covid-19 for around a month in order to ease the pressure on the healthcare system. 

Authorities have reimposed curbs that include limiting social interactions and dining out to two people in order to slow virus transmission.

About 84 percent of Singapore's population has been vaccinated against the virus.