CNN — Russian pilots tried to “dogfight” US jets over Syria, according to a spokesman for US Central Command, part of a recent pattern of more aggressive behavior.

The attempts have happened in several of the most recent instances of aggressive behavior from Russian pilots, Col. Joe Buccino said.

The Russian pilots do not appear to be trying to shoot down American jets, a US official told CNN, but they may be trying to “provoke” the US and “draw us into an international incident.”

In military aviation, dogfighting is engaging in aerial combat, often at relatively close ranges.

A video released by US Central Command from April 2 shows a Russian SU-35 fighter jet conducting an “unsafe and unprofessional” intercept of a US F-16 fighter jet.

A second video from April 18 shows a Russian fighter that violated coalition airspace and came within 2,000 feet of a US aircraft, a distance a fighter jet can cover in a matter of seconds.

Over the last several years, the US and have used a deconfliction line between the two militaries in Syria to avoid unintentional mistakes or encounters that can inadvertently lead to escalation.

US officials have reached out to their Russian counterparts over the recent incidents, and the Russians have responded, the official said, but “never in a way that acknowledges the incident.”

Since the beginning of March, Russian jets have violated deconfliction protocols a total of 85 times, the official said, including flying too close to coalition bases, failing to reach out on the deconfliction line, and more.

That also includes 26 instances in which armed Russian jets flew over US and coalition positions in Syria.

“It looks to be consistent with a new way of operating,” the official said. US pilots have refused to engage in the dogfights and are adhering to the protocols of the deconfliction measures, the official added.

The US has approximately 900 service members in Syria as part of the ongoing campaign to defeat ISIS.

The more aggressive behavior from Russian pilots has occurred outside of Syria as well.

In March, a Russian SU-27 fighter jet collided with a US MQ-9 Reaper drone in international airspace over the Black Sea.

The collision damaged the drone’s propellor, forcing it down in the water in an incident the US described as “unsafe, unprofessional” and even “reckless.”

“It’s concerning because it increases the risk of miscalculation, and given incidents like the MQ-9 intercept and subsequent downing over the Black Sea, it’s not the kind of behavior I’d expect out of a professional Air Force,” the commander of US Air Force Central Command, Lt. Gen. Alexus Grynkewich said in a statement earlier this month.

Russia subsequently presented state awards to the pilots of the Russian jets.