Just days after the Northern Marianas recorded its 50th case of Covid 19, the islands' total continues to rise with three more testing positive for the coronavirus on Sunday.
The Governor's Covid 19 Task Force said the new cases were all arriving passengers tested at Saipan International Airport.
All were moved safely to the designated isolation area for monitoring.
The Commonwealth Healthcare Corporation has started contact tracing of passengers on the same flight, as well as friends and family members of the newly confirmed cases.
Of the CNMI's 53 cases, 28 have been identified through port of entry screening procedures.
Authorities said the majority of these border cases originated from the US mainland with a handful from an unnamed US territory and the remainder from an unnamed foreign country.
Meanwhile, Governor Ralph Torres has renewed the declaration of a state of public health emergency and extended the declaration of the state of significant emergency.
Both are in effect until 15 September. Torres first placed the Commonwealth in a state of emergency on 29 January.