Earlier in the week, defensive tackle Marlon Davidson was placed on the COVID-19/reserve list but the team has indicated it was a separate positive result that led to Thursday's closure.
The Indianapolis Colts released a statement Friday afternoon that after retesting the samples have been confirmed to be negative for the COVID-19 virus and will continue to prepare for Sunday's game.
The team updated the news within hours and said it was a case of false positives.
"This morning, we were informed that several individuals within our organization have tested posted for COVID-19", the statement read.
The team said it is under the NFL's intensive protocols, which include all meetings being conducted virtually, personal protective equipment such as face masks or shields being worn on the practice field by players and staff at all times, and a daily deep-cleaning of the facility.
Other teams have closed their facilities due to concerns about COVID-19 but maintained their schedules.
The outcomes of the retests will likely determine the ability of Sunday's game against the Bengals to go off without a hitch. The Colts have a bye scheduled next week.
If the Indy-Cincinnati game requires a postponement, the National Football League should be able to push the game from Week 6 to Week 7 without any major scheduling changes.
Indianapolis Colts head coach Frank Reich and his team are working remotely on Friday after positive COVID-19 tests within the organization.
The Colts wrote on Twitter that the team will work remotely.