Sources

-https://militarywatchmagazine.com/article/russian-forces-close-in-sumy-elite-units-redeployed
-https://nypost.com/2025/06/30/world-news/russia-deploys-50000-troops-around-sumy-threatening-new-push-into-ukraine/
-https://www.wsj.com/world/europe/russia-ukraine-war-kursk-fba1185f
-https://united24media.com/latest-news/ukrainian-forces-hold-the-line-in-sumy-region-as-russia-masses-50000-troops-9503
-https://www.themoscowtimes.com/2025/06/30/russian-advances-toward-sumy-continue-wsj-a89614
-https://kyivindependent.com/ukraine-halts-russian-advance-in-sumy-syrskyi-says-summer-offensive-faltering-06-2025/
-https://apnews.com/article/russia-ukraine-war-sumy-border-front-line-75c3a87cd55b003e5bc7578f80bf9694