Health authorities said it was the first new confirmed case of coronavirus since early April.

The man, believed to be in his 30s, flew back from a Melbourne COVID-19 "hot spot" via Brisbane.

The Darwin man had been overseas in Pakistan and had quarantined in Melbourne where he had tested negative.

Complying with the current guidelines, the man has been quarantining at home since arriving in Darwin on Monday, where he lives alone.

The Public Health Unit is undertaking contract tracing for Qantas flight QF610 which travelled from Melbourne to Brisbane on Monday and Qantas flight QF 836 from Brisbane to Darwin on the same day.

Border restrictions in the NT end on July 17 but not for the identified hot spots.

Health Minister Natasha Fyles this morning said the new case was confirmed last night.

More reading: Nine more fined for breaching quarantine.

Ms Fyles said the last diagnosed case was on April 6.

She said the man spent a "couple of days" with family in a Melbourne hot spot while awaiting his flight to Darwin.

The man is now in isolation at Royal Darwin Hospital.

"There has been minimal contact with the community," she said.

He was in quarantine in a hotel after arriving in Darwin.

Contact tracing has begun on other passengers on the Qantas flight from Brisbane on Monday.

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