IS 'suicide attack' targets Kurdish-US convoy in Syria
The attack took place on a road in Hassakeh province, a London-based war monitor confirmed.
"We can confirm a combined US and Syrian partner force convoy was involved in an apparent VBIED attack today in Syria. There were no US casualties. We will continue to review the situation and provide updates as appropriate," a tweet by the anti-IS coalition posted on Twitter.
"The SDF finished their combing operations through three IS positions in Hasakeh province," the head of the Syrian Observatory for Human Rights Rami Abdel Rahman said.
"Now, for the first time since 2013, the province is completely empty of IS," he told AFP.
IS swept through the area five years ago as it was laying the groundwork for its self-styled Islamic "caliphate", which it declared across Syria and neighbouring Iraq in 2014.
But separate offensives have whittled down that territory to small, isolated pockets.
In early May, the SDF announced the final phase of its operation to fully expel the jihadis from Hassakeh and along the Euphrates River in the adjacent province of Deir az-Zour.
On 17 June, it pushed IS from its bastion of Dashisha in Hassakeh province and went on to clear other positions.
Mustefa Bali, who heads the SDF's press centre, confirmed to AFP at the time that there was no longer an IS presence in Hasakeh.
"Hassakeh has been fully liberated for the first time since 2013," he said.
Monday's attack followed two separate incidents in Damascus and Afrin on Sunday.
Three civilians were killed when a bus exploded in the northern Syrian city of Afrin on Sunday, on the first anniversary of the Turkish intervention in the Kurdish-majority region, a war monitor said.
Nine other people, including fighters, were wounded in the explosion.
The bomb blast came as fatalities were reported following a "huge explosion" near a military intelligence office in Damascus on Sunday, with state TV describing the attack as a "terrorist act".
"The explosion took place near a security branch in the south of the city. There are some people killed and injured but we could not verify the toll immediately," the minority told AFP.
It was unclear if the blast was caused by a bomb that was planted or a suicide attack, according to the monitor, which relies on a network of sources inside the country. However, shooting was reported following the explosion.
Syria is locked in a civil war that has killed at least 360,000 people by official counts suspended in 2014, and much more by unofficial counts, and displaced millions since a brutal crackdown on anti-government protests in 2011 spiralled into full conflict.
With key military backing from Russia, President Bashar al-Assad's forces have retaken large parts of Syria from rebels and jihadists, and now control almost two-thirds of the country.
The Syrian regime in May reclaimed a final scrap of territory held by the Islamic State group in southern Damascus, cementing total control over the capital for the first time in six years.
Observatory chief Rami Abdel Rahman said that Sunday's blast appeared to be the first attack in Damascus in over a year.
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