Russian drones entered the airspace of NATO members Romania and Latvia on Sunday and Saturday, prompting demand from some quarters for military response from the 75-year-old US-led alliance. The drones were reportedly aimed at Ukraine but one ended up crashing into Romania and another into Latvia, The Telegraph reported.

Bucharest scrambled F-16 fighter jets to assess the threat and issued a text alert to residents watching their smartphones Latvia’s defense minister confirmed that a Russian drone had landed near the town of Rezekne on Saturday and was believed to have been fired from Belarus, an ally of Russia.

“This situation is a confirmation that we need to continue the work we have started to strengthen Latvia’s eastern border, including the development of air defense capabilities and electronic warfare capabilities to limit the activities of UAVs [unmanned aerial vehicles] of different applications,” said Andrea Spruds, the Latvian defense minister.

Latvian President Edgar Rinkevics took to social media to declare: “We are in close contact with our allies. The number of such incidents is increasing along the eastern flank of NATO, and we must address them collectively.” A statement from the country’s defense ministry said: “Latvian airspace is part of Nato airspace.” Romania said the attack was a “renewed violation” by Russia as a result of its “illegal attacks” on Ukraine.

No one was apparently killed or injured as a result of the drones. Investigators found pieces of one drone outside of the Romanian village of Periprava, which sits across from the Danube river near the Ukrainian port town of Ismail, which is often hit by Russian drone attacks. NATO’s members to the east are increasingly exposed to the war in Ukraine as Russian President Vladimir Putin continues to win the war of attrition and NATO becomes more entangled in Ukrainian combat operations.

Russian missiles and drones have hit Poland, killing two people on one occasion, The Telegraph noted. Drones have entered Romanian airspace prior to Sunday’s incident when Russia has been attacking Ukraine’s ports along the Danube. So far, none of this has prompted NATO to invoke Article Five of its founding document that warns an attack on one member nation constitutes an attack on all members.

NATO Deputy Secretary General Mircea Geoana issued a statement instead, saying on Sunday: “NATO condemns the overnight Russian airspace violation into Romanian airspace. While we have no information indicating an intentional attack by Russia against Allies, these acts are irresponsible and potentially dangerous.”

Ukraine is investigating how a US-supplied F-16 fighter jet was destroyed and the pilot killed. It was on the brink of ceasefire talks with Russia before Ukrainian forces invaded the Kursk region of Russia, scuttling talks.