Supporters of President Donald Trump were filling streets Saturday around the Tulsa stadium where the president will hold his first rally in months, ready to welcome him back to the campaign trail despite warnings from health officials about the coronavirus.

The crowd — most without masks and dressed in Trump hats and T-shirts — were hoping to be among the first inside the more than 19,000-seat BOK Center for what is expected to be the biggest indoor event the country has seen since restrictions to prevent the COVID-19 virus began in March. Trump also will speak at an outdoor event to be held inside a perimeter of tall metal barriers that were put up around the BOK Center. Some of the attendees have been camped near the venue since early in the week.

Protesters flooded downtown streets on Saturday, blocking traffic in at least intersection. Some Black leaders in Tulsa have said they’re worried the visit could lead to violence. It’s happening amid protests over racial injustice and policing across the U.S. and in a city that has a long history of racial tension. Officials said they expected some 100,000 people in Tulsa’s downtown.

Renee Lamoreaux, a retiree and Trump supporter from Tulsa, said Friday that police officers had briefed ralliers, saying the event would basically be in a “big cage,” and the rest of the world would be outside. She said she felt reassured.

Tulsa has seen cases of COVID-19 spike in the past week, and the local health department director asked that the rally be postponed. But Republican Gov. Kevin Stitt said it would be safe. The Oklahoma Supreme Court on Friday denied a request that everyone attending the indoor rally wear a mask, and few in the crowd outside Saturday were wearing them.

The Trump campaign said six staff members helping prepare for the event tested positive for COVID-19. They were following “quarantine procedures” and wouldn’t attend the rally, said Tim Murtaugh, the campaign’s communications director.

Inside the barriers, the campaign was handing out masks and said hand sanitizer also would be distributed and that participants would undergo a temperature check. But there was no requirement that participants use the masks.

Teams of people wearing goggles, masks, gloves and blue gowns were checking the temperatures of those entering the the rally area. The Trump campaign had pledged to conduct temperature checks as people enter and to offer masks. As people gathered early in the day, few wore masks. Those who entered the secured area were given disposable masks, which most people wore as they went through the temperature check. Some took them off after the check.

The rally originally was planned for Friday, but was moved after complaints that it coincided with Juneteenth, which marks the end of slavery in the U.S., and in a city that was the site of a 1921 race-related massacre, when a white mob attacked Blacks, leaving as many as 300 people dead.

Stitt said he will join Vice President Mike Pence for a meeting Saturday with Black leaders from Tulsa’s Greenwood District, the area where the 1921 attack occurred. Stitt initially invited Trump to tour the area, but said, “We talked to the African American community and they said it would not be a good idea, so we asked the president not to do that.”