US President Donald Trump's campaign staff who attended the rally in Tulsa, Oklahoma, have been placed on quarantine this week after interacting with several colleagues, who later tested positive for the coronavirus, CNN reported.

File photo by AFP

"As a precaution, staff who made the trip to Tulsa are working remotely, and they will be tested and return working to the office after that," Murtaugh said. Multiple Secret Service agents also were ordered into quarantine after accompanying the president to the rally.