The man had been in quarantine for 14 days upon arrival in Melbourne from Pakistan. He was tested during this time and returned a negative result.
While waiting for his flight to Darwin he stayed with family in a defined Melbourne hotspot area.
Complying with the current guidelines, the man has been quarantining at home since arriving in Darwin on Monday, June 29, where he lives alone.
In accordance with national medical guidelines, the Public Health Unit is undertaking contract tracing for Qantas flight QF610 which travelled from Melbourne to Brisbane on Monday, June 29 and Qantas flight QF 836 from Brisbane to Darwin on the same day.
The man is now in under the care of Royal Darwin Hospital in isolation, says the release.
All 31 cases of COVID-19 in the NT are related to international or interstate travel, with no cases of community transmission.