The Defense Department ratcheted up its rhetoric against Iran on Monday, saying it will hold Tehran ultimately responsible for a spate of recent drone and rocket attacks on American troops in the Middle East.

While the Pentagon does not have information that the government of Iran “explicitly ordered” the attacks on U.S. forces in the past week, the groups responsible for the incidents are backed by Tehran, DOD spokesperson Brig. Gen. Patrick Ryder told reporters on Monday.

A number of U.S. troops were injured during the attacks, which spanned several days and bases in Iraq and Syria, and an American contractor died of a cardiac episode while running from a false alarm at al Asad air base in Iraq.

“By virtue of the fact that they are supported by Iran, we will ultimately hold Iran responsible,” Ryder said.

Ryder’s comments on Monday were a departure from the Pentagon’s more cautious rhetoric against Tehran since Hamas militants’ surprise attacks on Israel on Oct. 7 launched an escalating regional conflict.

In a press briefing last Thursday after the destroyer USS Carney intercepted missiles and drones launched by Yemen’s Houthi rebels in the northern Red Sea, Ryder declined to assign blame for the drone attacks on U.S. troops in Iraq and Syria. He also said he would not draw a direct link between the Oct. 7 strikes and the recent attacks on U.S. troops.

On Monday, however, Ryder pointed to statements last week by Iranian proxy groups saying they would scale up attacks on American forces if Israel launches a ground invasion of Gaza.

He declined to say which specific Iranian proxy groups were responsible for the attacks, even as he confirmed another had taken place in Syria. In the latest incident, which occurred at 3 a.m. Eastern time on Monday, American troops at the al Tanf garrison in southern Syria shot down two drones targeting their positions, Ryder said. There were no injuries.

“We are concerned about escalation,” Ryder said. “We are all watching increased tensions in the region and again we want to deter this from becoming a bigger conflict.”

After the attacks last week, Defense Secretary Lloyd Austin ordered additional ships and air defenses to U.S. Central Command to better protect American forces in the region. That included redirecting the aircraft carrier USS Dwight D. Eisenhower strike group from the eastern Mediterranean — where it was set to join the USS Gerald R. Ford off the coast of Israel — to an area that includes the Red Sea, the Persian Gulf and other Middle Eastern waters .

Austin also ordered the deployment of a Terminal High Altitude Area Defense battery and Patriot missile defense system battalions to locations throughout the region, and placed an additional number of forces on “prepare to deploy” orders.

“We’re going to continue to do what we need to do to protect and safeguard our forces and take all necessary measures,” Ryder said. Although “no one wants to see a wider regional conflict, but we will not hesitate to protect our forces.”

No direct Iran order for proxies to attack US troops, Pentagon says.

The United States has not seen a direct order from Iran's Supreme Leader Ayatollah Ali Khamenei to attack U.S. troops in the region, the Pentagon said on Monday following a rise in attacks in Iraq and Syria by suspected Iran-backed groups.

U.S. forces have been repeatedly targeted by missiles and drones since the Israel-Gaza conflict began on Oct. 7 with Palestinian Hamas militants attacking southern Israel.

"We don't necessarily see that Iran has explicitly ordered them to take these kinds of attacks," Pentagon spokesperson Brigadier General Patrick Ryder told reporters.

Pressed on the issue, Ryder added: "We haven't seen a direct order, for example, from the Supreme Leader saying: 'Go out and do this.'"

Ryder, however, said that the United States ultimately holds Iran responsible for such attacks by militant groups "by virtue of the fact that they are supported by Iran."

Iranian security officials told Reuters Iran's strategy was for Middle East proxies like Hezbollah to pursue limited strikes on Israeli and U.S. targets but to avoid a major escalation that would draw in Tehran, a high-wire act for the Islamic Republic.

On Sunday, senior Biden administration officials including Defense Secretary Lloyd Austin warned of the risk of significant escalation in attacks on American troops in the Middle East and of Iran seeking to widen the Israel-Hamas war.

At the weekend, Austin ordered new air defenses to the Middle East to safeguard troops. He said the Pentagon will send a Terminal High Altitude Area Defense (THAAD) system and additional Patriot air defense missile system battalions to the region.

The United States has also sent warships and fighter aircraft to the region to try to deter Iran and Iran-backed groups from widening the conflict. This includes the deployment of two aircraft carriers and about 2,000 Marines.

"No one wants to see a wider regional conflict, but we will not hesitate to protect our forces," Ryder said.

In the latest incident, U.S. troops were targeted by two attack drones in Syria on Monday but they were intercepted by base defenses and caused no injuries.

Last week, U.S. forces confronted multiple drones targeting troops in Iraq, some causing minor injuries and a U.S. warship shot down more than a dozen drones and four cruise missiles fired by Iranian-backed Houthis off the coast of Yemen.

The heightened tensions have put U.S. personnel on constant alert. During a false alarm at Al-Asad airbase in Iraq on Thursday, a civilian contractor died from a cardiac arrest.