US military forces on February 2 launched retaliatory air strikes in Iraq and Syria against Iran's Islamic Revolutionary Guards Corps (IRGC) Quds Force and affiliated militia groups.

The strikes came in response to a drone attack that killed three US soldiers and wounded dozens more at a remote base in Jordan on January 27.

At 4pm (EST), numerous US aircraft, including long-range bombers flown from the United States, struck more than 85 targets with more than 125 precision munitions, US Central Command (CENTCOM) said in a statement.

The targeted facilities include command and control operations centers, intelligence centers, rockets, missiles, unmanned aerial vehicle (UAV) storage, and logistics and munition supply chain facilities of militia groups and their IRGC sponsors who facilitated attacks against US and coalition forces, it said.

"Our response began today. It will continue at times and places of our choosing," US President Joe Biden said in a statement.

"The United States does not seek conflict in the Middle East or anywhere else in the world. But let all those who might seek to do us harm know this: If you harm an American, we will respond," he added.

National Security Council spokesman John Kirby told journalists the strikes lasted about 30 minutes, though they involved a lengthy trip for the B-1 Lancer bombers that took part after flying from the United States.

He said the Defense Department is still assessing damage from the strikes -- which hit dozens of targets at seven separate facilities -- but that the United States believes the raids were successful.

At least 20 Iran-affiliated fighters were reported killed in Syria, and an unconfirmed number of militants in Iraq, according to local sources.

Targets had been carefully chosen to avoid civilian casualties, Kirby said.

US Defense Secretary Lloyd Austin said the February 2 action was "the start of our response."

"The president directed additional actions to hold the IRGC and affiliated militias accountable for their attacks on US and coalition forces," he said in a separate statement.

"We will continue to take action, do whatever is necessary to protect our people, and hold those responsible who threaten their safety," said CENTCOM commander Gen. Michael "Erik" Kurilla.

Deterring Iran and its proxies

On January 27, three US soldiers were killed and dozens others injured when a drone packed with explosives hit the remote Tower 22 base in Jordan near the border with Syria, where some 350 US troops are deployed as part of the campaign against the "Islamic State of Iraq and Syria" (ISIS).

The United States blamed the attack on the Islamic Resistance in Iraq, a loose alliance of pro-Iran militias, of which Kataib Hizbullah is the main group.

Regional countries, including Iraq and Jordan, condemned the January 27 attack carried out by Iran-backed militants, with Iraq urging the "end to the cycle of violence" in the region.

US and coalition forces have been attacked at least 165 times in Iraq, Syria and Jordan since mid-October with weapons including drones, rockets and short-range ballistic missiles.

While the United States does not seek war, the operation aims to deter Iran and its proxies and to erode their ability to launch future attacks on US forces and interests.

"They have a lot of capability," Austin said February 1 of Iran and its allies. "I have a lot more."

The United States has repeatedly sought to contain the conflict both through diplomacy and shows of force. This was not the first time it has turned to military action in the conflict.

After repeated warnings failed to deter Yemen's Iran-backed Houthis from attacking international shipping in the Red Sea, the United States, in coordination with the United Kingdom, and support from Australia, Canada, the Netherlands and Bahrain, conducted joint strikes on Houthi targets January 12.

The strikes aimed "to degrade their capability to continue their illegal and reckless attacks on US and international vessels and commercial shipping in the Red Sea," CENTCOM said in a statement.