Saturday evening's blast struck refugees who had fled the fighting in the oil- and gas-rich Syrian province and who had gathered on the east bank of the Euphrates River, the Britain-based Syrian Observatory for Human Rights said.

At least 75 civilians were killed and some 140 others were injured, the monitor said. IS fighters detonated the car bomb at close range, the Observatory's director Rami Abdel Rahman told news agencies.

Syria's state news agency SANA later described the blast as a suicide car bombing.

The blast happened in an area between the Conoco and Jafra energy fields controlled by the US-backed Syrian Democratic Forces (SDF) and close to the city of Deir el-Zour, which last week was captured by Syrian regime forces from the "Islamic State" (IS) armed group.

The largest city in eastern Syria, Deir el-Zour is a center for the country's oil extracting industry.

Read more: US-backed SDF captures Syria's largest oil field from 'Islamic State'

Refugees still in danger

Save the Children estimates that 350,000 people have fled the recent fighting in Deir el-Zour.

"The situation in the city and surrounding countryside has been especially bleak, with civilians trapped between the fighting and all too often caught in the crossfire," explained Sonia Khush, the charity's Syria director.

The Observatory, which gets its information from a network of Syria-based activists, said civilians were stranded on an island on the Euphrates directly facing Deir el-Zour and where some jihadist pockets remained.

IS is facing an onslaught by both Syrian government troops and the SDF alliance for the few remaining areas it controls in eastern Syria.

Read more: 'Islamic State' suffers major losses in Syria and Iraq

Having been driven from about 96 percent of territory they once captured in Syria and Iraq, the jihadists still control a small stretch inside the war-ravaged country and some desert regions along the Iraq-Syria border.

Last IS areas remain

After taking full charge of Deir el-Zour city, the Syrian army said IS militants were now isolated and encircled in the countryside east of the city.

Meanwhile, Kurdish-led SDF forces were reported to be making fresh gains further north in Deir el-Zour province.

Syrian regime forces, backed by intensive Russian airstrikes, are now attempting to retake Abu Kamal, the last urban center controlled by the jihadi group in Syria, and close to the Iraqi border.

Last month, Syrian Kurd-led forces, allied with the US, captured Raqqa, once the de facto capital of IS' self-proclaimed caliphate in Syria.

Also on Saturday, reports suggested that US President Donald Trump and his Russian counterpart may discuss a settlement to the 6-year Syrian civil war in the next few days.

Russia's RIA news agency said the talks could take place on the sidelines of the Asian economic summit in Vietnam.

Washington and Moscow remain on opposing sides in the conflict and ties remain frosty over allegations of Russian interference in the 2016 US presidential election.

What is the 'Islamic State'? Where did it come from? The "Islamic State" (IS) — also known as ISIL, ISIS and Daesh — is an al-Qaida splinter group with a militant Sunni Islamist ideology. It emerged in the aftermath of the US-led invasion of Iraq in 2003 and is led by Abu Bakr al-Baghdadi. Their goal is to create a worldwide "caliphate." It gained worldwide notoriety in 2014 after a blitzkrieg military campaign that resulted in the capture of Mosul.

What is the 'Islamic State'? Where does it operate? IS is believed to be operational in more than a dozen countries across the world. It controls territories in Iraq and Syria. However, the group has lost much of the territory it controlled in Iraq and Syria at the height of its expansion in 2014.

What is the 'Islamic State'? Who is fighting back? The US leads an international coalition of more than 50 countries, including several Arab nations. Russia, Iran and its Lebanese Shiite ally Hezbollah, which all support the Syrian government, also fight IS. Regional forces such as the Kurdish peshmerga (above) and US-backed Syrian Kurdish fighters, fight IS on the ground. The Iraqi army and militia have pushed IS from large parts of the country.

What is the 'Islamic State'? How does it fund itself? One of IS' main sources of income has been oil and gas. At one point, it controlled an estimated one-third of Syria's oil production. However, US-led airstrikes deliberately targeted oil resources and the Syrian government as well as US-backed Syrian Kurdish fighters have retaken most oil wells. Other means of income include taxes, ransom, selling looted antiquities and extortion.

What is the 'Islamic State'? Where does it carry out attacks? IS has claimed responsibility for numerous terrorist attacks across the globe. The militant group has targeted capitals across the EU, including Berlin, Brussels and Paris. IS leaders have encouraged so-called "lone wolf" attacks, whereby individuals who support IS carry out terrorist acts without the direct involvement of the group.

What is the 'Islamic State'? What other tactics does it use? The group uses various tactics to expand its power. IS fighters have looted and destroyed historical artifacts in Syria and Iraq in an attempt at "cultural cleansing." The group has also enslaved thousands of women from religious minority groups, including Yazidis. IS also uses a sophisticated social network to distribute propaganda and recruit sympathizers.

What is the 'Islamic State'? How has it impacted the region? IS has further exacerbated the ongoing Syrian conflict. Millions of Syrians and Iraqis have fled their homes, many traveling to Europe in pursuit of refuge. Although it has lost all of its strongholds, the militant group has left extraordinary destruction in its wake. Areas affected by the militant group's rule will likely take years to rebuild. Author: Rachel Stewart



mm/bw (AFP, AP, Reuters)