UPDATE: 2:05 p.m. EST —​ Russia’s defense ministry fired back Saturday at claims it violated Turkey’s airspace Friday, according to the state-run RIA Novosti. The agency reported that defense representative Igor Konashenkov called reports of a breach of the Syrian-Turkish border “unfounded propaganda.”

Original story:

Turkey and Russia don’t appear to be taking the weekend off from their ongoing dispute. The Turkish foreign ministry announced Saturday it had summoned the Russian ambassador to condemn a Friday incident in which it claims a Russian plane purposefully violated its airspace.

The Yeni Şafak newspaper reported a Russian Su-34 jet flew over Gaziantep in south central Turkey for 20 or 25 seconds Friday about 11:46 a.m., local time. The ministry reported Turkish radar units had repeatedly warned the aircraft, both in English and Russian, not to enter the area. The airspace is protected by the North Atlantic Treaty Organization.

In response, Turkey held a meeting Friday night with the ambassador in which it protested Russia's decision to ignore the warnings and fly over Turkish territory.

“This new violation is yet another concrete example of Russian escalatory behavior,” the ministry wrote in a statement. “We once again explicitly call on Russia to act responsibly. ... We underline that such actions could lead to serious consequences, the responsibility of which will totally rest with the Russian Federation.”

Friday wasn't the first time Turkey has complained over Russia's actions overhead. In November, two Turkish F-16s took down a Russian Su-24 near Turkey's border with Syria where Russia has been conducting airstrikes in support of the Syrian government. Russia argued it never left Syrian airspace and enacted sanctions, BBC News reported.

NATO released a statement of its own calling Russia's decision to fly over Turkey Friday a dangerous one. “I call on Russia to act responsibly and to fully respect NATO airspace,” Secretary-General Jens Stoltenberg said, adding NATO was backing Turkey in the conflict. “Russia must take all necessary measures to ensure that such violations do not happen again.”

Turkish President Recep Tayyip Erdoğan used stronger language when he spoke to reporters Saturday, the Daily Sabah reported. “If Russia continues to violate Turkey's sovereignty, it will have to face the consequences,” he said, adding he had requested a meeting with Russian President Vladimir Putin.