The White House said the incident occurred on July 26. According to AP, this is the sixth reported incident this month and the second in 24 hours in which the US accused Russian fighter jets of flying dangerously close to US UAVs and manned aircraft, putting both pilots and aircraft at risk.

Two U.S. officials confirmed that the Russian fighter jet’s actions on July 26 damaged a U.S. MQ-9 Reaper UAV. The officials were not authorized to discuss the matter publicly and spoke to reporters on condition of anonymity.

"We have seen reports, initial reports, of a second Russian fighter jet this week flying dangerously close to our UAV," White House press secretary Karine Jean-Pierre said.

The incident occurred while the US military was conducting a mission against Islamic State (IS) militants in Syria, a US spokeswoman said. Ms. Jean-Pierre said that "Russia's close approach and deployment of flares to a US UAV during a routine mission" was a violation of international rules.

In previous incidents, Russian aircraft have intercepted US aircraft at dangerously close ranges, including one instance with a manned aircraft that the US said could have endangered the lives of four US crew members.

A senior Russian military leader has blamed Washington for the latest incident and accused US-led coalition aircraft in Syria of violating deconfliction protocols with Russia 10 times in 24 hours.

Rear Admiral Oleg Gurinov, head of the Russian military's Center for Reconciliation in Syria, said that a US UAV flew very close to two Russian fighter jets in the Syrian sky early on the morning of July 26. Mr. Gurinov said that the systems on the two Russian Su-34 and Su-35 fighters detected the targeted aircraft and activated the automatic flare firing function.

"The United States continues to misinform the public about illegal flights of its UAVs in Syrian airspace, in violation of deconfliction protocols, while accusing the Russian side of dangerous actions," Gurinov said in a statement carried by the Interfax news agency.