Humvee ISIS ISIL
Iraqi servicemen inspect the wreckage of a Humvee belonging to Islamic State militants.Reuters

Fresh details of the recent capture of an Iraqi military base by Islamic State (IS) militants have emerged, suggesting Baghdad failed to send air support to counter the assault that eventually resulted in the death of dozens of soldiers.

Camp Saqlawiyah near the town of Sijir, Anbar province, 45 miles (70 kilometers) west of Baghdad fell after it was attacked by IS suicide bombers disguised in Iraqi army uniforms and driving stolen Humvees at the weekend.

In a video posted online a man identifying himself as soldier who managed to escape and survive claims that, after the first explosion hit the base gates, he phoned his commander asking for help.

"He said, 'Yes, yes, air support is on its way,'" the man says. "Since I made the call to him until I reached (a) base about three hours later, I did not see a single plane."

A similar account was given in a separate video by a second serviceman who was shot and wounded during the gunfight.

"From 2:30 a.m. until 10 a.m., no one came to help us," the man said, according to the CNN. "... No one responded, and they sent us nothing." Both videos and the soldiers' accounts could not be independently verified.

The exact number of troops that died in the attack is disputed, with some reports saying 40 soldiers were killed and 68 captured and others suggesting up to 300 died.

The Washington Post reported that at least 820 soldiers were stationed at Camp Saqlawiyah when it came under attack.

The newspaper said almost a week earlier, IS militants had taken over a nearby bridge cutting off all access routes to the camp.

Earlier this week, some 30 captive men in Iraqi military uniforms were paraded by IS extremists through the streets of the nearby city of Fallujah.

Iraqi Prime Minister Haider al-Abadi ordered an investigation into the incident and said the government was committed to reinforcing military and police forces in Anbar.

Some analysts said the onslaught casts doubts on the Iraqi army's ability to retake control of territory seized by IS, previously known as Isis, without the deployment of international troop son the ground.

"I think the events since the Islamic State invasion ... have shown the Iraqi military is incapable of going toe-to-toe (with ISIS)," the Long War Journal editor Bill Roggio said.