Russian aircraft conducted several "unsafe and unprofessional" encounters with both U.S. and NATO aircraft on Feb. 10, according to additional information provided by the Air Force.

Gen. Tod Wolters, commander of U.S. Air Forces in Europe and U.S. Air Forces Africa, said in a March 2 roundtable with reporters at a conference that there were three separate encounters with Russian Su-24 attack aircraft, and a fourth with an Ilyushin Il-38 maritime patrol aircraft on Feb. 10.

That was the same day Russian aircraft buzzed the destroyer Porter in the Black Sea — an encounter that had previously been reported. But Wolters' comments appeared to be the first time NATO-Russian aircraft encounters that day had been reported.

Russian fighter jets buzz the destroyer Porter in a flyby

A Russian fighter jet buzzed the U.S. destroyer Porter. (U.S. European Command)

On March 3, there was confusion among Air Force officials at the Air Force Association's Air Warfare Symposium in Orlando, Florida, as to whether Wolters had misspoken the previous day and was only referring to the Porter close calls. The Office of the Secretary of Defense later released a statement confirming Wolters' comments that aircraft encounters indeed took place that day, in addition to the Porter encounter.

"General Wolters' comments stand for themselves, and his main points bear repeating," OSD said in its statement, which USAFE provided to Air Force Times. "He assessed that the trend of unprofessional engagements with Russian aircraft has plateaued over the past six months. Between all of the U.S., other NATO allied, and Russian military aircraft traffic in international airspace, interactions are a relatively frequent occurrence, and the vast majority of those are deemed to be safe and professional. As the senior Air Force commander in Europe, General Wolters assessed that the very few unprofessional engagements that do occur can largely be attributed to issues of judgment, rather than malicious intent."

The OSD statement said that one of those Feb. 10 close calls was with a NATO aircraft, and the rest were with U.S. aircraft. OSD did not confirm Wolters' count of four troubling encounters that day, and only referred to "a number of intercepts" of U.S. aircraft. The statement referred to "a relatively large number of interactions with Russian aircraft that day, some of which were deemed to be safe and standard and some of which were assessed as unsafe and unprofessional."

USAFE spokesman Lt. Col. Michael Andrews said in a Sunday email that the Air Force would not provide further specific information on each intercept, but confirmed that officials were concerned by the Russian aircraft's rate of closure and proximity off the wing of NATO aircraft.

"Those two causes represent the [vast] majority of unsafe intercepts as determined by the air crews," Andrews said.