The 44-year old FedEx pilot arrived from Australia in early April and was instructed to remain in his hotel at the airport, but instead took a train to the centre to visit some shops.

Singapore on Wednesday recorded 675 new cases, taking the small city state's total to more than 25,000 - by far the highest number in South East Asia. The official death toll stands at 21.

The majority of the infections are among Singapore's more than 300,000 foreign workers.