Ammon News - AMMONNEWS - Gunmen seized an Iraqi-Syrian border post in Iraq's western Anbar province on Sunday, security sources said, a day after Sunni militants fighting the Baghdad government grabbed another border crossing further north.

Officials at the border post of al-Waleed fled after a relatively small number of militants in two cars fired into the air, a customs police source and an army source said. They did not say who was behind the attack. A government official who spoke on condition of anonymity blamed "terrorists".

Al-Waleed lies west of Rutba, one of three towns to fall on Sunday to the Sunni insurgents led by Al-Qaida splinter group the Islamic State in Iraq and Syria (ISIS), which has made stunning advances across northwest and central Iraq this month.

Al-Qaim, another border town about 200 km (120 miles) further north, fell on Saturday to the ISIS militants, who want to an Islamic caliphate spanning Iraq and Syria.

The security sources said some officials from the customs office and from a government bank at the Waleed border crossing had fled westward in the direction of Syria and others had headed east into Iraq.

The office for the prime minister's military command did not immediately respond to requests for comment.

Jordan mobalizes

Jordan mobilizes its military forces along its border with Iraq amid reports of Islamist insurgents' capture of a key border crossing.

Jordanian military sources say the kingdom has mobilized "tens" of units near the country's Karama border crossing with Iraq.

Kerry Arrives

U.S. Secretary of State John Kerry arrived in Amman late Sunday for talks with Jordanian officials on the unfolding crisis.

Kerry is to hold meetings with Jordanian Foreign Minister Nasser Judeh and military officials to discuss the security impact of rapid gains made by Islamist militias in western and northern Iraq and a brewing humanitarian crisis threatening to drive thousands across the Iraqi-Jordanian border.

Officials accompanying Kerry are also expected to meet Iraqi political and tribal opposition figures during the visit.

In Egypt on Sunday for the previous leg of his trip, Kerry said that Arab countries should resist funding Sunni fighters in what is turning into a cross-border war between Iraq and Syria because that support eventually could help the fast-spreading insurgency in Iraq.

He argued that the Islamic State of Iraq and Syria has become a threat to the entire Mideast, and perhaps beyond.

"This is a critical moment," Kerry said after meeting with Egyptian President Abdel-Fattah al-Sissi.

He said the group is a "threat not only to Iraq, but to the entire region."

"There is no safety margin whatsoever in funding a group like ISIL, and we particularly discourage individuals in the region who may have been sending money through some illicit charity or through various back-channel initiatives under the guise this is for the general welfare and benefit for people who have been displaced, but then that money finds its way into the hands of terrorists," Kerry said, using an alternative name for ISIS.

"We are obviously discouraging any kind of support to entities where it is unsure where the money is going ... and that goes to any government, any charity, any individual. We must not allow that kind of funding to be a part of this equation," Kerry said.

U.S. officials later made clear that Kerry was not calling for an end to aid — financial or otherwise — to Syria's moderate Sunni rebel forces. They have fought for more than three years to oust Syrian President Bashar Assad, whose minority Alawite sect is an offshoot of Shiite Islam.

It is possible that some support to Syrian rebels may wind up in insurgents' hands due to the amount of overlap between Sunni fighters within and between the two counties.

A U.S. official speaking on condition of anonymity to discuss sensitive diplomatic matters said the U.S. is comfortable that the moderate opposition in Syria has enough control over its international assistance to prevent that from happening.

*Reuters