A Russian fighter jet came within 15 feet of a U.S. Air Force spy plane over the Black Sea in southeastern Europe this week, a Pentagon representative said Thursday evening. The reported incident between the Russian Su-27 and the American RC-135 is the latest involving Moscow’s air force, which during the past year has been cited for harassing other military aircraft and traversing the sovereign airspace of countries around Europe.

The RC-135 aircraft was on a regular route in international airspace when the Russian jet fighter intercepted it in an “unsafe and unprofessional manner,” said U.S. Navy Capt. Daniel Hernandez, a representative of the U.S. European Command. He added that the incident had been carefully investigated, according to a report by the Washington Free Beacon, a conservative news outlet based in the nation’s capital.

The Su-27 aircraft purportedly flew alongside the RC-135 before the Russian jet performed what the Pentagon described as an aggressive turn away, which is highly dangerous and disturbed the U.S. plane’s controls.

Unrelated to the close encounter between the two aircraft, the U.S. Defense Department held a video conference with its Russian counterpart Thursday in an effort to “avoid accidents and unintended confrontation between coalition and Russian forces whenever the two sides operate in close proximity,” said Pentagon Press Secretary Peter Cook, referring to the air campaigns being conducted by both countries in Syria. “The conversation was constructive, and the two sides agreed to continue safety discussions in this format in the future,” Cook said.

In a separate incident, Japanese jets were scrambled after two large Russian Tu-95MS Bear bombers approached the northern tip of Japan and flew just outside the country’s sovereign airspace, the nation’s defense ministry reported Tuesday.