BEIRUT - A militant assault led by suicide bombers killed dozens Tuesday at a camp for the displaced near Syria's border with Iraq, as pressure grows on the Islamic State group in both countries.

The violence left at least 38 people dead and came as another surprise IS attack on Tuesday killed 10 soldiers in Iraq, to the south along the border. The militant group appears to be lashing out as it faces escalating offensives on its last two major bastions: second city Mosul in Iraq and Raqa in neighbouring Syria.

IS's dawn attack in Syria's northeast hit a makeshift camp near the border with Iraq where some 300 families were waiting to cross into territory held by the Syrian Democratic Forces, a US-backed alliance that is leading the assault on Raqa.

The Syrian Observatory for Human Rights, a monitoring group, said at least five suicide bombers blew themselves up inside and outside the camp in Hasakeh province which hosts Syrians and Iraqis forced from their homes.

Heavy clashes then erupted between the IS fighters and the SDF near the camp, which lies just inside Syrian territory, Observatory head Rami Abdel Rahman told AFP. He said at least 38 people had been killed including 23 displaced Syrians or Iraqi refugees.

"At least 30 people were wounded, and the death toll may rise because some people are in critical condition and others are still unaccounted for," the Britain-based monitor said.

Deadly Iraq attack

Kamal Derbas, a press officer for the Kurdish Red Crescent, put the civilian death toll at 22. He told AFP the attack began at 4:00 am local time (0100 GMT) and that 35 people were wounded.

Civilians fleeing IS in both Syria and Iraq have made their way to the desolate border region seeking protection and onward passage to safety in Kurdish-controlled territory. But conditions in the area are harsh, with little shelter, overstretched authorities, and the risk of renewed violence.  The other IS attack in Iraq saw militants fire on an army base near the remote outpost of Rutba, near the country's western borders with Syria and Jordan.

An Iraqi army lieutenant colonel told AFP that IS fighters fired mortar rounds and rockets at the 1st Division base in the Saggar area, east of Rutba, before trying to storm it.

IS appeared to be trying to breach the defence of Rutba, which is the last sizeable town on the road from Baghdad to the Jordanian border, as well as to create diversions to ease pressure on its fighters in Mosul, military officials said.

A massive offensive was launched in mid-October to retake Mosul, where IS head Abu Bakr al-Baghdadi declared the establishment of IS's so-called "caliphate" nearly three years ago.

'Violent' Tabqa clashes

IS once controlled swathes of land on both sides of the Iraqi-Syrian border, but US-backed offensives have seen much of that territory retaken.

A US-led coalition began bombing IS positions in Iraq in August 2014 and launched raids against the militants in neighbouring Syria the following month. In northern Syria, the coalition is backing the major assault by the SDF - an alliance of Arab and Kurdish fighters - on Raqa.

A key waypost in that offensive is the city of Tabqa, which lies along the Euphrates River and on an IS supply route about 55 kilometres (35 miles) west of Raqa.

On Tuesday, the SDF was locked in "very violent clashes" with IS in a northern district of Tabqa, the last section of the city still held by the militants, the SDF said in a statement.

SDF fighters managed to seize a tank and several vehicles used by IS, it said. More than 80 percent of Tabqa is now in SDF hands, just eight days after the group first entered the city.

More than 320,000 people have been killed in Syria since the country's conflict began in March 2011 with anti-government protests.

Iran to keep up military support for Syria regime

 Iran will maintain its support for the Syrian government despite the deaths of hundreds of its advisers and volunteers in the six-year civil war, a commander said in comments published Tuesday. Iran and its Lebanese ally Hezbollah are the Syrian regime's most important military supporters after Russia in its battle against the rebels.

"We will send advisers in all fields and offer all help at our disposal so the resistance front doesn't break," the ground forces commander of the elite Revolutionary Guards, General Mohammad Pakpour, told the Fars news agency.

"They are present there now and we will deploy more as long as there is a need for advisory support."Pakpour said that advisers from the Guards' ground forces, including the Saberin Special Forces Unit, were working alongside those from the Guards' Quds Force foreign operations arm.

Syrian chief of staff General Ali Abdullah Ayoub was in Tehran for talks on Tuesday.

In his meeting with Defence Minister Hossein Dehghan, Ayoub said Syria was "indebted to Iran's support," the Guards' SepahNews website reported.

Dehghan said: "The nations of Iran and Syria are fighting on the same front to remove the lethal threat of terrorism and restore peace and security to the region."

As well as advisers, Iran has sent thousands of "volunteer" fighters recruited among its own nationals as well as the Shia communities in neighbouring Afghanistan and Pakistan. It also has military advisers and trainers deployed in Iraq.

As of early March, at least 2,100 fighters sent from Iran had been killed in Iraq and Syria, according to Iranian officials.