The US military on Thursday hit several targets in the Syrian city of Mayadin in parts of Deir ez-Zor province in the third day of skirmishes with Iran-backed groups.

According to local military sources, at least three members of an Iran-aligned militia were killed when they were targeted by a US helicopter as they were about to prepare a rocket launcher in the town. 

Iranian militias have a strong presence in the town and have repeatedly targeted the nearby Al Omar oilfield on the eastern bank of the Euphrates where the US coalition has its biggest base in Syria.

The base also known as Green Village was targeted on Wednesday night in a second consecutive day of violence between the US military and Iran-backed militants that injured at least one US service member and killed up to four militants. 

According to CENTCOM, Iran-affiliated militants in the area were struck by AH-64 Apache attack helicopters, AC-130 gunships, and M777 artillery. “We will respond appropriately and proportionally to attacks on our servicemembers. No group will strike at our troops with impunity. We will take all necessary measures to defend our people,” said Michael “Erik” Kurilla, the commander of US Central Command. 

Military tensions escalated between US forces and Iranian militia in Syria as nuclear talks between Tehran and Washington seemed to be making some progress.

Earlier in the week, Iran’s state-run media said a senior member of Iran’s Revolutionary Guard’s Ground Force was killed in Syria in the early hours of August 22, claiming that the general was killed as he was serving as a "military advisor" in the country.

Later on Thursday, Syrian media reported loud explosions near Masyaf and Tartous, in Western Syria. According to the Syrian observatory for human rights, it was an Israeli air strike.