BAGHDAD: Iraq's Shi'ite paramilitary groups have deployed to the border to back up border guard forces who came under fire from within Syria over the past three days, one of their commanders said on Friday.

"After several Iraqi border guard positions came under several attacks by missiles, and backup from security forces was late, the 13th brigade of the Popular Mobilisation Forces (PMF) was deployed and targeted the origins of the launch," PMF commander for west Anbar, Qassem Mesleh, said in a statement.

"Operations command and the infantry brigade are now present on the Iraqi-Syrian border in border guard positions to repel any attack or movement by the enemy. This area is not within the PMF's remit but it is our duty to back up all security forces."

The PMF is an umbrella grouping of mostly Iran-backed and trained Shi'ite militias that formally report to Iraq's prime minister but are separate from the military and police.