Soldiers deployed to the al-Tanf garrison in Syria watch for the impact of a mortar from an observation point during a readiness exercise in 2020. (William Howard/U.S. Army)

WASHINGTON — Nearly 60 U.S. troops at military bases in Syria and Iraq have been injured in 56 missile and drone attacks launched in the last month by Iran-backed militant groups, the Pentagon said Tuesday.

Militant groups in the region began increasing attacks on U.S. bases in the two countries in mid-October, within two weeks after Hamas militants from Gaza launched a surprise attack on Israel that killed hundreds of civilians. Since then, American troops have been targeted dozens of times at bases in Iraq and Syria.

On Tuesday morning, a multi-rocket attack was launched against a U.S. base at Mission Support Site Euphrates in Syria. No casualties and damage to infrastructure were reported, said a defense official who spoke on the condition of anonymity. It brings the number of attacks on U.S. forces to 29 in Syria and 27 in Iraq by a mix of one-way attack drones and rockets.

Tuesday’s incident comes after four attacks occurred between Sunday and Monday. Three strikes targeted U.S. bases at al-Shaddadeh, Mission Support Site Green Village and Mission Support Site Euphrates in Syria. The bases at Green Village and Euphrates are in eastern Syria near its border with Iraq and Shaddadeh is farther north.

There were also three attacks last week against U.S. troops at al-Harir air base in northern Iraq. There were no casualties from the drones used in the attack but there was damage to infrastructure, the defense official said.

The U.S. is tracking 59 personnel who have been injured during the strikes.

“Approximately, 27 personnel have been evaluated for [traumatic brain injuries] and 32 for other non-serious injuries. As of today, all 59 have returned to duty,” Deputy Pentagon Press Secretary Sabrina Singh said.

In response to the attacks against American forces, the U.S. has conducted multiple airstrikes in Syria at sites tied to Iran-backed militants.

Most recently, two strikes occurred in Syria on Sunday. Defense Secretary Lloyd Austin said the strikes targeted a training facility near the city of Albu Kamal and a safe house near the city of Mayadeen. The previous strikes occurred Oct. 26 and Nov. 8.

While defense officials have said the airstrikes are meant to deter further attacks, the militant groups continue strikes against U.S. forces in the region.

Singh said the Pentagon believes the deterrence strikes are working because the fighting between Israel and Hamas has not spread into a wider regional conflict.

“I think we are being very deliberate on how and when we conduct our strikes against these groups. And I think that Iran is certainly seeing that message,” she said.