CHICAGO (AP) — Rising COVID-19 infections in other states have prompted Chicago to restart a travel order after several weeks without travel restrictions, city officials announced Tuesday.

The Chicago Department of Public Health said starting Friday unvaccinated travelers from Missouri and Arkansas have to either quarantine for 10 days or have a negative COVID-19 test.

Both states have met the city’s mark of at least 15 daily infections per 100,000 residents. Health officials said other states could be added if cases continue to rise, including Nevada, Louisiana, Utah and Florida.

At the same time, cases are also rising in central and southern Illinois.

“The COVID-19 pandemic is not over, and this only goes to show that the virus is still very much a threat and that we must all remain vigilant against it,” Dr. Allison Arwady, the health department’s commissioner, said in a statement. “That means getting vaccinated and wearing a mask in public settings if you are not fully vaccinated.”

Chicago officials have previously warned that people who defy the order could face hefty fines, but city officials said in November that only warning letters had been sent out. A message left Tuesday for a city health department spokeswoman wasn’t immediately returned.