The US military says that it has downed an armed pro-Syrian regime drone that was nearing coalition partnered forces in At Tanf in southeastern Syria near the Iraqi-Syrian border, the second such incident in less than two weeks in the area, and only three days after the US downed a Syrian warplane near Raqqa, raising tensions between the US and Russian militaries.
It is the fifth time in the past month the USA has struck at forces allied with the Syrian government in the area.
Boeing F-15E Strike Eagle intercepted and destroyed an armed UAV controlled by "pro-regime forces", which had been threatening US -backed forces fighting in Syria on June 8.
Attempting to de-escalate the situation, USA officials in Baghdad have sent out notices reminding parties involved in Syria that there is a de-confliction mechanism in place with Russian forces to reduce the chances of "strategic miscalculation".
The presence of Iranian-backed troops, artillery and tanks and US -led coalition forces in southern Syria, namely around the At Tanf crossing at the Iraq-Syria border, has slowly turned the area into a flash point.
Just before the shooting down of the Syrian bomber, U.S. officials say there was a movement of regime ground troops with tanks and artillery towards two towns near Raqqa that were held by US-backed Syrian Democratic Forces (SDF).
The Russians "don't have operational control over the Syrian forces or the pro-regime militias", Davis noted.
The downing of the warplane - the first time in the six-year conflict that the U.S. has shot down a Syrian jet - came amid another first: Iran fired several ballistic missiles Sunday night at Islamic State positions in eastern Syria in what it said was a message to Saudi Arabia and the US.
The bombs were so close the US sent an F-18 to shoot down the Syrian jet - the first time that's happened during the Syrian civil war.
Australia has suspended all air operations over Syria in the wake of USA forces downing a Syrian jet and a warning from Russian Federation that US -led coalition planes are now targets for its forces in parts of the country.
Tensions escalated on Sunday as the US Army brought down the jet near Raqqa and Iran launched missiles at IS targets in eastern Syria - the first time each state has carried out such actions in the multi-sided Syrian war.
Iran's Revolutionary Guard described the strike as revenge for Islamic State attacks on Tehran earlier this month that killed at least 18 people and wounded more than 50.
Tuesday's encounter is the latest development in what's become an increasingly hostile standoff between the US military and the various forces supporting Syrian President Bashar al-Assad's fight to stay in power.
The Defence Department issued a statement Tuesday saying ADF air operations had been suspended as a "precautionary measure". On Tuesday, the United States reported that a Russian fighter jet came within five feet of a USA warplane over the Baltic Sea.
It said the Coalition forces were manning an outpost northeast of At Tanf where it provides training and advice to its partnered forces against the ISIS group.
Damascus maintains its forces were targeting terrorists in the area and directly accuses the USA of supporting Daesh, the local name for the Islamic State.
Australia is part of a USA -led coalition that has been waging war against Islamic State militants in Syria and Iraq. "Given recent events, the coalition will not allow pro-regime aircraft to threaten or approach in close proximity to coalition and partnered forces".
"The US" repeated combat operations under the guise of "combating terrorism' against the legitimate armed forces of a United Nations member-country are a flagrant violation of global law and an actual military aggression against the Syrian Arab Republic".
The coalition's alliance with armed groups that have previously been involved in anti-regime operations means that the formation of a unified front against ISIS in Syria is extremely unlikely.