A Russian fighter jet struck the propeller of a U.S. surveillance drone over the Black Sea on Tuesday in a brazen violation of international law, causing American forces to bring down the unmanned aerial vehicle, the U.S. said.

The incident, which raised tensions over Moscows war in Ukraine, appeared to mark the first time since the height of the Cold War that a U.S. aircraft was brought down after being hit by a Russian warplane.

U.S. President Joe Biden was briefed on the incident by national security adviser Jake Sullivan, according to White House National Security spokesman John Kirby. He added that U.S. State Department officials would be speaking directly with their Russian counterparts and expressing our concerns over this unsafe and unprofessional intercept.

State Department spokesman Ned Price called it a brazen violation of international law. He said the U.S. summoned the Russian ambassador to lodge a protest and the U.S. ambassador to Russia, Lynne Tracy, has made similar representations in Moscow.

The U.S. European Command said in a statement that two Russian Su-27 fighter jets conducted an unsafe and unprofessional intercept of a U.S. MQ-9 drone that was operating within international airspace over the Black Sea.

It said one of the Russian fighters struck the propeller of the MQ-9, causing U.S. forces to have to bring the MQ-9 down in international waters. Prior to that, the Su-27s dumped fuel on and flew in front of the MQ-9 several times before the collision in a reckless, environmentally unsound and unprofessional manner, the U.S. European Command said in a statement from Stuttgart, Germany.

This incident demonstrates a lack of competence in addition to being unsafe and unprofessional, it added.

U.S. Air Force Gen. James B. Hecker, commander of U.S. Air Forces Europe and Air Forces Africa, said the MQ-9 aircraft was conducting routine operations in international airspace when it was intercepted and hit by a Russian aircraft, resulting in a crash and complete loss of the MQ-9. He added that in fact, this unsafe and unprofessional act by the Russians nearly caused both aircraft to crash.

There was no immediate reaction from Moscow, which has repeatedly voiced concern about U.S. intelligence flights close to the Crimean Peninsula, which Russia illegally annexed from Ukraine in 2014. The Kremlin has charged that by providing weapons to Ukraine and sharing intelligence information with Kyiv, the U.S. and its allies have effectively become engaged in the conflict.

Kirby emphasized that the incident wouldnt deter the U.S. from continuing their missions in the area.

if the message is that they want to deter or dissuade us from flying, and operating in international airspace, over the Black Sea, then that message will fail, Kirby said, adding that is not going to happen.

Were going to continue to fly and operate in international airspace over international waters, he said. The Black Sea belongs to no one nation.

The U.S. European Command said the incident followed a pattern of dangerous actions by Russian pilots while interacting with U.S. and Allied aircraft over international airspace, including over the Black Sea.

These aggressive actions by Russian aircrew are dangerous and could lead to miscalculation and unintended escalation, it warned.

Gen. David Berger, commandant of the Marine Corps, said that this type of collision is his greatest concern, both in that area of Europe as well as in the Pacific.

Probably my biggest worry both there and in the Pacific is an aggressive Russia or China pilot or vessel captain, or something gets too close, doesnt realize where they are, and causes a collision, Berger said, in response to a question at a National Press Club event on Tuesday.

He said that whether an incident is intentional or not, it forces nations leaders to try and sort it out quickly from afar.

Amid the continuing fighting in Ukraine, a Russian missile on Tuesday struck an apartment building in the center of Kramatorsk, killing at least one person and wounding nine others in one of Ukraines major city strongholds in its eastern Donetsk region.

The victims were among at least seven civilians killed and 30 wounded in 24 hours, Ukraine authorities said.

Ukrainian President Volodymyr Zelenskyy posted a video showing gaping holes in the facade of the low-rise building that bore the brunt of the strike. The impact damaged nine apartment blocks, a kindergarten, a local bank branch and two cars, said regional Gov. Pavlo Kyrylenko.

Russian troops are striking residential buildings, schools and hospitals, leaving cities on fire and in ruins, Kyrylenko said.

Russian President Vladimir Putin, speaking Tuesday during a meeting with workers at a helicopter factory in southern Siberia, once again cast the conflict in Ukraine as an existential one for Russia, charging that unlike the West -- which, he said, is seeking to advance its geopolitical clout -- its fighting for its existence as a state.

For us, its not a geopolitical task, Putin said, its the task of survival of Russian statehood and the creation of conditions for the future development of our country.

Russia had welcomed a Chinese peace proposal to end the fighting, but Kremlin spokesman Dmitry Peskov said Tuesday that Kyivs refusal to have talks leaves Moscow with only military options.

We must achieve our goals, Peskov told reporters. Given the current stance of the Kyiv regime, now its only possible by military means.

The Russian onslaught has focused on the devastated eastern city of Bakhmut where Kyivs troops have been fending off Russian attacks for seven months and which has become a symbol of Ukraines resistance, as well as a focal point of the war.

Zelenskyy discussed the situation in Bakhmut with the top military brass and they were unanimous in their determination to face down the Russian onslaught, according to the presidential office.

The defensive operation in (Bakhmut) is of paramount strategic importance to deterring the enemy. It is key for the stability of the defense of the entire frontline, Valerii Zaluzhnyi, the commander-in-chief of the Armed Forces of Ukraine, said.