More than 30 civilians and Kurdish-led fighters have been killed in an attack by Islamic State on a makeshift refugee camp near Syria's border with Iraq.
Militants targeted the camp for displaced Syrians and Iraqi refugees at Rajm al-Salibi, near the town of Shaddadi in Hassakeh province.
They also clashed with members of the Syrian Democratic Forces (SDF) stationed at a nearby checkpoint.
Islamic State (IS) said the attack was one of several targeting "apostates" around Shaddadi.
The Syrian Observatory for Human Rights, a UK-based monitoring group, reported that at least five IS suicide bombers blew themselves up outside and inside the camp at Rajm al-Salibi, east of Shaddadi, at dawn on Tuesday.
At least 38 people were killed by the bombings and subsequent clashes, among them 23 civilians, and 30 other people were wounded, it added.
According to Syria's official Sana news agency, more than 30 civilians were killed and 34 wounded. It did not say whether there had been any suicide bombings.
The Kurdish Red Crescent put the civilian death toll at 22.
SDF fighters took wounded civilians to hospitals in the city of Hassakeh. Several were admitted to intensive care due to the severity of their injuries, according to medical sources cited by Sana.
An IS statement said six groups of militants had attacked SDF positions in Shaddadi and its surrounding area on Tuesday, including a "barracks" near Rajm al-Salibi, killing and wounding dozens of people.
An Iraqi army source told the BBC the militants had also abducted dozens of civilians during the attack on the camp.
It was not possible to verify the report. However, a similar allegation was made by the head of the Iraqi parliament's human rights committee in an interview with Beirut-based al-Mayadeen TV and Sana cited some of those injured as saying they had lost contact with dozens of their relatives.
About 300 families were waiting at Rajm al-Salibi - where conditions are harsh and there is little shelter - to be screened and allowed to enter SDF territory.
They included Syrians from Raqqa and Deir al-Zour provinces, as well as some of the thousands of Iraqis who have fled to Syria from Mosul since October.
The charity Save the Children said that, as a result of the attack, approximately 400 people were being relocated from Rajm al-Salibi to another camp at al-Hawl.
"Camps for refugees and the internally displaced are meant to be a source of shelter for people fleeing war, violence and persecution," said Sonia Khush, the organisation's Syria country director.
"All parties to the conflict must guarantee that refugee and IDP camps are places of refuge, not war."
Islamic State is coming under mounting pressure in northern Syria from the SDF's Kurdish and Arab fighters, who are supported by the US, and from pro-government forces in neighbouring Iraq.
The SDF has driven IS militants out of much of the province where the attack took place and is close to taking control of the strategically important Euphrates River Valley town of Tabqa.
It will soon launch an offensive to retake the city of Raqqa, the de facto capital of the 'caliphate' proclaimed by IS after the fall of the Iraqi city of Mosul in 2014.