One of the arrivals from Colombia – a 19-year-old man – started displaying symptoms on Sunday.
The other two imported infections – a 22-year-old woman from Colombia and a 42-year-old woman from Indonesia – were asymptomatic.
The woman from Indonesia had been staying at the iclub Ma Tau Wai Hotel in To Kwa Wan.
The Department of Health said the city had also recorded fewer than five preliminary positive cases.
Over the past fortnight, Hong Kong has recorded 32 cases, of which three were local cases.
The city has had 11,868 cases since the start of the pandemic, with 210 related deaths.