Biden says not seeking conflict with Iran after tit-for-tat Syria strikes

President Joe Biden has said the United States is not seeking conflict with Tehran, after Washington carried out strikes on what it said were Iran-linked groups in Syria in retaliation for a deadly drone attack.

"Make no mistake: the United States does not ... seek conflict with Iran, but be prepared for us to act forcefully to protect our people," Biden told reporters during a visit to Canada on Friday.

Asked whether there should be a higher cost for Iran, Biden replied: "We’re not going to stop." 

The US strikes, that activists say killed at least four people, came after the Pentagon said a US contractor died, and another contractor and five military personnel were wounded by a kamikaze drone "of Iranian origin" that struck a US-led coalition base near Hasakeh in northeastern Syria.

In response, US Defense Secretary Lloyd Austin said on Thursday that, at Biden's direction, he had ordered the "precision air strikes tonight in eastern Syria against facilities used by groups affiliated with Iran's Islamic Revolutionary Guard Corps".

Hours after the strikes, the US Central Command [CENTCOM] said 10 rockets were fired at American and coalition forces at the Green Village base in northeast Syria.

There were no injuries or damages to facilities at the base, but one rocket struck a home around five kilometres away, causing minor wounds to two women and two children, CENTCOM said.

The activist group Deir Ezzor 24, which covers news in the province, said the American strikes killed four people and wounded a number of others, including Iraqis.

Pro-Iranian forces say they can respond to further US strikes 

Late on Friday, pro-Iranian forces in Syria said in an online statement that they have a "longarm" to respond to further US strikes on their positions.

The statement, signed by the Iranian Advisory Committee in Syria, said US strikes had left several fighters dead and wounded, without specifying their nationality.

"We have the capability to respond if our centres and forces in Syria are targeted," the statement said. 

Militias affiliated with Iran's Revolutionary Guard have a heavy presence across Syria, especially around the border with Iraq, and south and west of the Euphrates in Deir Ezzor province, where the latest US strikes took place.

The United States has about 900 troops in posts across northeastern Syria.

The Pentagon said two F-15 fighters launched the retaliatory attack — which spokesperson Pat Ryder said was to protect US personnel — in the early morning hours local time.