A coordinated Isis suicide bombing has left an estimated 32 people dead at a refugee camp on Syria's north-eastern border with Iraq.

Reports say that five suicide bombers detonated explosives inside and outside a displaced person's camp for Syrian and Iraqi refugees at Rajm al-Salibi, near Shaddadi, in Hassakeh province.

The dead included at least 23 civilians who had fled violence in the two neighbouring countries and Kurdish-led fighters who have taken up arms under the Syrian Democratic Forces (SDF) banner.

Isis fighters also clashed with western-backed SDF troops near the makeshift camp stationed at a nearby checkpoint.

The British-based Syrian Observatory for Human Rights (SOHR) reported that the jihadists had used explosive belts and that the death toll is expected to rise due to the nature of victim's injuries. It said at least 38 people were killed by the bombings and subsequent clashes, among them 23 civilians, and 30 other people were wounded.

"At least five suicide attackers blew themselves up outside and inside a camp for Iraqi refugees and displaced Syrians in Hasakah province," SOHR chief Rami Abdel Rahman told AFP.

Other estimates put the death toll between 22 and 30 civilians with the wounded being driven to hospitals in the nearby city of Hassakeh.

Isis claimed the attack saying that six groups of militants had attacked SDF positions in the area including "barracks" killing and wounding "apostates" around Shaddadi.

The SDF, which contain both Arab fighters and Kurdish brigades, has driven the Islamist militants out of much of the Hassakeh province with the Euphrates River Valley town of Tabqa their next target.

The BBC reported an Iraqi army source as saying that dozens of civilians had been kidnapped during the attack.

SDF
File photo: Fighters from the Democratic Forces of Syria (SDF) inspect weapons and ammunition that, according to them, belonged to Isis fighters, in al-Shadadi town, in Hasaka province, Syria February 26, 2016.REUTERS/Rodi Said

The camp was said to have contained fleeing Syrians from Raqqa, to the west, and the embattled Deir al-Zour province, to the south, and thousands of Iraqis who have fled from Mosul since October last year.

Save the Children said around 400 people were being relocated to another camp at al-Hawl after the bombings.

Sonia Khush, the organisation's Syria country director said: "Camps for refugees and the internally displaced are meant to be a source of shelter for people fleeing war, violence and persecution.

"All parties to the conflict must guarantee that refugee and IDP camps are places of refuge, not war."

The SDF, who are supported by US-led airstrikes, are preparing for an assault on the Isis de facto capital of Raqqa, in Syria, before the end of the year. Raqqa has been an Isis stronghold since the city became the first to be liberated from Syrian President Bashar al-Assad's control in 2013.