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US forces shot down two drones targeting a Central Command base in southern Syria, the Pentagon said as it warned of Iran-backed militias trying to exploit the turmoil in the Middle East.
Monday's attempted attack is the latest in a series of recent strikes on US forces in the Middle East believed to have been carried out by groups backed by Iran.
The drones were headed towards Al Tanf, in a strategic area near the Syrian border crossing with Iraq and Jordan.
“I can confirm that there was an attempted drone attack at Al Tanf in Syria. Two, one-way attack drones, taken down,” Pentagon press secretary Brig Gen Pat Ryder said, adding there were no injuries to US troops.
Brig Gen Ryder said the drones were destroyed with “defensive systems”.
He said the Pentagon does not have concrete evidence that Tehran has explicitly ordered militias under their influence to carry out these kinds of attacks.
“That said, by virtue of the fact that they are supported by Iran, we will ultimately hold Iran responsible,” Brig Gen Ryder said.
When pressed on the issue, said: “We haven't seen a direct order, for example, from the supreme leader [Ayatollah Ali Khamenei] saying: 'Go out and do this'.”
The US is trying to contain the Israel-Gaza conflict but increasing strikes by Iran-backed militias in Lebanon, Syria and Iraq show Tehran could be seeking to exploit the turmoil.
A senior US defence official said the situation could become significantly worse.
“We see a prospect for much more significant escalation against US forces and personnel in the near term,” the official said.
“Let's be clear about it: The road leads back to Iran. Iran funds, arms, equips and trains militias and proxy forces all across the region.”
The official said the recent surge in attacks was “efforts by Iran and Iran proxy forces to seek to escalate this conflict”.
Al Tanf was also the target of an attack last week, and Iranian militias are suspected of launching drones in Iraq, including near Al Asad airbase.
Iraq on Monday condemned as “unacceptable” attacks against bases on its territory housing US forces.
Since Wednesday, at least five rocket and drone attacks have targeted three Iraqi military bases where American troops are stationed as part of the international coalition set up to fight ISIS.
“The attacks that target Iraqi bases that house advisers from the international coalition in Iraq are unacceptable,” Iraq's military spokesman Yahya Rasool said in a statement, according to AFP.
Prime Minister Mohammed Shia Al Sudani “directed all the security services to … pursue the elements responsible for these attacks”, he added.
Most of the attacks have been claimed by a group called the Islamic Resistance in Iraq on Telegram channels affiliated with Shiite factions loyal to Iran.
The Pentagon has stationed naval assets, including two aircraft carrier strike groups, in the region in an attempt to prevent this.
Defence Secretary Lloyd Austin said on Sunday that a Terminal High Altitude Area Defence system and extra Patriot air defence missile system battalions will be sent to the region and more troops put on standby.
Al Tanf garrison was established when ISIS fighters took control of eastern Syria along the border with Iraq.
After the militants were driven out, it became part of the larger US strategy to contain Iran's military reach in the region.
On Thursday, A US warship operating in the Red Sea intercepted drones and missiles that had been launched by the Iran-backed Houthi rebels in Yemen and were possibly headed towards targets in Israel, the Pentagon said.