NATO's deputy commander in Europe is warning that Russian President Vladimir Putin is becoming increasingly reckless as the war in Ukraine drags on and as he seeks to divide Western allies. Air Chief Marshal Sir John Stringer spoke to The Associated Press Tuesday at a security conference in Estonia amid warnings from some European leaders that Moscow is planning to test NATO’s collective defense pact with bolder attacks that have already included sabotage and espionage. Leaders from Poland and France have suggested Moscow might test NATO with deliberate drone or missile strikes. However, officials in Estonia, Latvia, and Lithuania remain cautious about a serious escalation. Stringer emphasizes the need for NATO to avoid overreacting, as Putin aims to provoke the alliance.