Suspected Israeli strike on Syria kills Iran-backed Iraqi fighters
Lebanon's Al-Mayadeen news channel reported that Israel was responsible for the strikes in Albu Kamal on the Iraqi-Syrian border.
Head of the Syrian Observatory for Human Rights said the aircraft carrying out the strikes was "unidentified", while AFP reported a confirmation from the US-led coalition that they did not carry out the strikes.
"Unidentified aircraft targeted vehicles and arms depots in the Albu Kamal area, causing a large explosion. At least eight Iraqi Hashed fighters were killed," Rami Abdel Rahman said, adding that several others were wounded.
The US-led military coalition operating in Syria and Iraq denied carrying out the strike through a spokesman contacted by AFP.
Abdel Rahman said three villages in the Albu Kamal area known for housing forces loyal to Tehran have been targeted by drone strikes since Wednesday, causing no casualties.
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The deadly strike comes in a context of spiralling tension between the United States and Iran, much of which has played out in Iraq.
Late last year, a US air strike in Iraq killed 25 Hashd fighters from the Kataib Hezbollah militia, considered one of the closest to Tehran.
Hashd supporters subsequently stormed the huge US embassy compound in central Baghdad, further escalating the situation.
On 3 January, a US strike near Baghdad airport killed Qasem Soleimani, Iran's feared external operations supremo, in one of the Middle East's highest-profile assassinations of recent years.
Also killed in the strike was Abu Mahdi al-Muhandis, a founder of Kataib Hezbollah and seen as Iran's man in Iraq.
Tehran has vowed bloody revenge and has so far responded with ballistic missiles on a base in western Iraq housing US and other coalition troops.