According to a report by FOX News, Russia used cluster munitions on a base used by American and British Special Forces last month. The bombing run came after an agreement between Russia and the U.S. to double check with one another before making specific bombing runs.
The base is located near the Syrian border with Jordan, and is used by the U.S. and British as a forward launching point for Special Operations forces to create a buffer between ISIS and Jordan. Luckily, according to the report, 24 British and US Special Forces members had just left the night before the bombing occurred.
As the jet was heading straight towards the base USCENTCOM called Russia’s air campaign headquarters in Latakia, Syria to tell them not to attack the base. 90 minutes after that call the bombing run occurred which killed four rebels. The Russian pilot did not respond to US calls that were made on a frequency agreed upon in case of emergencies. Russia argued they thought it was ISIS trying to confuse them with radio chatter, the US dismissed this notion. The next excuse from Russia was that Jordan gave them the go ahead to attack the base, the US came back saying they asked Jordan and that story was false.
Since the incident, the US has told Russia to stay clear of the Jordanian border. Its unknown if an accident that occured later involving a interception by two USN F/A-18 of a RUF attack aircraft in Syria was related. Either way, things are heating up between the two powers.