The weekend drone attack that killed three US service members in Jordan occurred when American air defenses confused the enemy aircraft with a friendly one coming in at the same time, a report said Monday.

The drone launched by Iran-backed militants approached a small US-allied outpost near Jordan’s border with Syria on Saturday just as an American drone was returning to the base — causing confusion among staff there and a crucial delay in trying to shoot down the enemy device, unidentified military officials told the Wall Street Journal on Monday.

The terrorists’ drone struck soldiers’ living quarters, killing three American troops and leaving at least 34 others injured.

“I think what was different about this attack is where it landed — it did impact in where our living quarters are,” Pentagon spokeswoman Sabrina Singh told reporters at a briefing Monday. “I believe it was pretty early morning, so people were actually in their beds when the drone impacted.

“[US] Central Command is looking into what can be done when it comes to our air defenses and looking into this incident to determine how best we can move or how fast we can further strengthen our air defense systems,” Singh said.

The rep insisted the site was no less protected than other regional bases that have been recently attacked without fatalities.

There have now been 165 attacks on US forces — 66 in Iraq, 98 in Syria and Saturday’s in Jordan — since Oct. 17, Singh said. In addition to the three Americans slain in Jordan, there have been a total of about 80 American service members receiving non-serious injuries in those assaults, she said. 

“To my knowledge, there was nothing different or new about this attack than [from what] we’ve seen in other facilities that house our service members,” Singh said. “Unfortunately, this attack was successful, but we can’t discount that [earlier] other attacks, whether it be Iraq or Syria, were not intended to kill our service members.”

President Biden said the attack was launched by “radical Iran-backed militant groups operating in Syria and Iran” — and a Telegram channel used by pro-Iranian terrorist groups later claimed the assault was in retaliation for a US strike in the south of Baghdad a few days before in which two terrorists were killed, according to the Journal.

The perpetrators of Saturday’s attack were likely supported by Kataib Hezbollah, one of Iran’s main militia allies based in Iraq, White House National Security Council spokesman John Kirby told CNN on Monday.

He said Biden would respond “in a time and manner of his own choosing” and “in a very consequential way.

“We don’t want to see these attacks continue. And we want to make it clear that they’re unacceptable,” Kirby said.

“We also want to make it clear that we’ll do what we have to do to protect our troops, our facilities, our national security interests in the region.

“But we don’t seek a war with Iran,” he said. “We’re not looking for a wider conflict in the Middle East.”

The president himself vowed Sunday to respond to the attack, which marked the first time American soldiers were killed by enemy fire in the Middle East since Hamas launched its Oct. 7 attack on Israel, prompting other militant groups to join in the fray.

Several Republicans have urged Biden to swiftly retaliate against Iran for the fatal attack.

“Hit Iran now. Hit them hard,” Sen. Lindsey Graham (R-SC), who is well known for his hawkish views, wrote on X on Sunday.

“Iran is undeterred,” he said. “The only thing the Iranian regime understands is force. Until they pay a price with their infrastructure and their personnel, the attacks on U.S. troops will continue.”

Iranian officials have denied responsibility for the attack.

Iranian Foreign Ministry spokesman Nasser Kanaani on Monday called allegations that the country was involved “baseless accusations” designed to expand the Israel-Hamas war.

“The responsibility for the consequences of provoking allegations against Iran lies with those who bring up such baseless claims,” he said.

No specific group has claimed responsibility for the attack at the base, which is situated near Al Tanf Garrison in southeastern Syria, where US forces worked with allies to fight off Islamic State militants.