With just 12 days to go until the Boston Marathon, organizers have announced that Russian and Belarusian athletes will be barred from participating. “Like so many around the world, we are horrified and outraged by what we have seen and learned from the reporting in Ukraine,” Boston Athletic Association president 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.” Runners who live in either country will be barred from competing in both the marathon and the 5K race held two days prior. Belarusian and Russian citizens who don’t live in their home countries will be allowed to run but not under either nation’s flag, organizers said.