OKLAHOMA CITY (AP) — A spike in coronavirus cases in the Tulsa area is linked to indoor events and people who attend such gatherings should take health precautions, Oklahoma health officials warned Friday.

The Tulsa Health Department’s warning comes eight days before President Donald Trump is scheduled to hold a campaign rally at the city’s BOK Center, which has a listed seating capacity of over 19,000.

Anyone who is sick or might have been exposed to someone with COVID-19 should stay home, Department Director Bruce Dart said.

Department spokesperson Leanne Stephens said an undetermined number of the latest coronavirus cases were linked to two recent indoor gatherings, but declined to name them.

Stephens said the department has not had contact with the Trump campaign and the warning is unrelated to the planned rally.

Trump angered black community and political leaders by scheduling the rally on Juneteenth, the day that marks the end of slavery in America.

Late Friday, the president announced on Twitter that the event would be pushed back a day to June 20 in order to avoid holding a rally on Juneteenth.