BOSTON (AP) — Athletes from Russia and Belarus previously accepted to compete in this year’s Boston Marathon who are currently residing in either country will no longer be allowed to participate, the Boston Marathon Association announced Wednesday.

The exclusion from the world’s oldest annual marathon also extends to athletes previously accepted into the B.A.A.’s 5K event. However, it doesn’t affect Russian or Belarusian athletes registered for the events who are not residents of the countries. They will be allowed to compete, but won’t be able to run under their country’s flag.

“Like so many around the world, we are horrified and outraged by what we have seen and learned from the reporting in Ukraine,” B.A.A. president and CEO Tom Grilk said in a statement. “We believe that running is a global sport, and as such, we must do what we can to show our support to the people of Ukraine.”

The B.A.A. said it won’t recognize the country affiliation or flags of Russia and Belarus until further notice. This year’s Boston Marathon, 5K, and Invitational Mile do not include any professional or invited athletes from those countries.

Organizers said they will make reasonable attempts to refund entry fees to athletes no longer able to participate.

The B.A.A. will also provide all Ukrainians who are registered in the marathon or 5K and are unable to compete with a refund or option to defer to a future year.