Coalition forces fire a mortar from a base in the al-Shaddadeh region in Syria on Feb. 14, 2023. (Nicholas J. De La Pena/U.S. Army)

WASHINGTON — Militant groups aligned with Iran have carried out more attacks in the last day on U.S. military bases in Iraq and Syria, pushing the number of strikes to more than 50 in the past month amid rising tensions in the Middle East and despite American retaliation, a military official said Monday.

The militant groups began increasing attacks on U.S. bases in the two countries in mid-October, not long 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.

“Most of these attacks were successfully disrupted by our military. Most failed to reach their targets, thanks to our robust defenses,” a U.S. military official said Monday on condition of anonymity. “Between Oct. 17 and [today], U.S. and coalition forces have been attacked at least 52 times.”

The official said 28 attacks occurred in Syria and 24 in Iraq and the groups used a “mix of one-way attack drones and rockets.”

The most recent strike occurred on Monday at Rumalyn Landing Zone in northeastern Syria.

“One [enemy] drone was shot down. The other impacted [the landing zone],” the military official said. “No casualties and minor damage to [four tents].”

The four most recent 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 in Green Village and Euphrates are in eastern Syria near its border with Iraq and Shaddadeh is farther north.

The attacks have yet to cause any serious injuries. Officials said Monday that 56 U.S. personnel have been injured in the strikes.

The Pentagon has said the groups attacking U.S. bases are supported, trained and funded by Iran. Several Iranian-backed militant groups operate in the region, including Hamas in Gaza, Hezbollah in Lebanon and the Houthis in Yemen. Last week, Houthi rebels shot down a U.S. MQ-9 Reaper drone off the coast of Yemen.

In response to the attacks against American forces, the U.S. carried out another set of airstrikes against enemy targets in Syria on Sunday — a training facility and a safe house, according to the Pentagon. Both locations were used by militant groups and Iranian military forces, defense officials have said.

The strikes marked the third time in recent days that U.S. fighter jets hit enemy targets in Syria. The first occurred Oct. 26 and the second Nov. 8.

“What we are trying to do is make sure that this does not spiral into escalation,” said Air Force Brig. Gen. Pat Ryder, the Pentagon’s top spokesman. “I don’t think anybody wants to see that.”

The United States has sent an additional 1,200 troops to the Middle East in recent weeks along with two aircraft carrier strike groups and more aircraft to support Israel in its fight against Hamas and deter an escalation of the conflict. On Friday, five special operations soldiers were killed in a Black Hawk helicopter crash during training in the Mediterranean Sea.