Saudi Arabia has deployed some 30,000 troops to its border with Iraq, after Iraqi forces abandoned their posts on their side of the border, according to reports.
The deployment comes as Saudi-owned news channel Al Arabiya aired an interview with an Iraqi border police officer, in which he testified that his forces had been given unexplained orders to abandon their posts, despite there not being any present danger to them. The officer expressed confusion as to why the orders had been ordered.
The gulf state's sizable deployment is yet another alarming sign that the rapid disintegration of the Iraqi state and accompanying sectarian warfare - spurred on by a Sunni rebellion led by the radical Islamic State of Iraq and the Levant (ISIS), which recently declared an "Islamic State" or "Caliphate" - is threatening to spread beyond that country.
ISIS has already taken over vast swathes of territory in Syria, amid the bloody civil war there, and Jordan has already deployed forces to its border with Iraq following threats by ISIS members to attack the Hashemite regime.
Israeli officials have also expressed their concern over potential threats to national security posed by ISIS's rapid expansion through Syria and Iraq, while Iran has reportedly sent an unspecified number of its own forces to Iraq to help Shia militias and government forces fight Sunni rebels.
Saudi leader King Abdullah has ordered "all necessary measures" to his country's borders from "terrorist threats", according to state news agency SPA.