MOSUL, Iraq - Weapons and Sunni Muslim insurgents are seeping from Iraq into Syria, Iraqi officials and arms dealers say, fueling violence in a country that once sent guns and militants the other way.The revolt against Syria's President Bashar Assad has struck a chord with Sunni tribes in Iraq's border provinces of Anbar and Ninawa, where strong family ties across the poorly guarded frontier have long favored contraband and trafficking.Difficult bordersAssad's government says it is fighting "terrorists" who have killed more than 2,000 members of the security forces. The Free Syrian Army, a loose collection of army defectors and local militias, has taken the lead in armed opposition to Assad.Syria has already demanded that Lebanon curb gun-smuggling across its border and has accused its northern neighbour Turkey of doing too little to halt arms flows across its frontier.The Arab League opened the door for governments to arm anti-Assad rebels when it passed a resolution in Cairo on Sunday urging Arabs to "provide all kinds of political and material support" to the opposition.Lieutenant-General Ahmed Al-Khafaji, a senior Iraqi interior minister official, told Al-Hurra television channel this week that border patrols had been reinforced to prevent any fighters crossing into Syria from Iraq.But the frontier with Syria has long been a major smuggling route difficult to control. Earlier this year, residents near the border town of Qaim said they were helping send food and other suppliers to kinsmen across the frontier in Albu Kamal after the main border point was closed there."There are many weapons smuggling operations run here, but it is not significant amounts. We have many patrols to secure the border line. But still there are many areas that are very rugged," said one Mosul security source.Iraqi police along the 1,114 km frontier say they are exposed to clashes with increasingly active smugglers and gunmen in the barren scrubland and desert around the Euphrates.One gun dealer in Mosul who called himself Abu Mohammed told Reuters prices had doubled in the last month as Syrian smugglers demanded more arms, mainly assault rifles such as Kalashnikovs."There is no big demand to get pistols because they consider it as a personal weapon," he said. "But this does not mean that even the prices of pistols have not gone up as well."But one prominent tribal sheikh in the Sunni heartland of Anbar said local demand for weapons was also increasing because Sunni tribes were trying to regain the military muscle they lost when US troops were still stationed in Iraq."There is demand for weapons in Anbar but not for smuggling. It is for internal use," he said. "People in Anbar are looking to get back their weapons after the Americans took them away."Iraq, awash with weapons since the 2003 invasion that ousted Saddam Hussein, is still plagued by violence from al-Qaida affiliates, Sunni Islamists, fighters tied to Saddam's Ba'athist party, Iranian-backed Shi'ite militias and criminal gangs.Now Iraqi security officials say there are signs Sunni insurgents are beginning cross the border to join Assad's opponents, and gun smugglers are cashing in as prices double for weapons reaching concealed in commercial cargoes.Gauging the flow of Iraqi insurgents and illegal weapons into Syria is difficult, but the border was once hot with insurgent traffic in the opposite direction as foreign fighters flocked to attack US and Iraqi targets after the invasion."We think fighters linked to al-Qaida and some Sunni armed groups are sending fighters to Syria to participate in the fighting there as a kind of moral support," said one senior Baghdad security official, who asked not to be identified because he is not authorized to talk to the media."Corrupt officials are working at the crossings in (the northern region of) Mosul and Anbar, so we can expect people to take advantage of this to smuggle weapons and fighters, but we do not think it is at a significant level," he said.Syria's crisis creates a delicate balancing act for Iraq's Shi'ite-led government as its neighbor's revolt takes on an increasingly sectarian tone and Assad faces growing pressure from the Arab League and Western powers.Baghdad has strong political and trade ties with Shi'ite power Iran, an ally of Assad, who belongs to a minority Alawite sect dwarfed by Syria's Sunni majority of more than 70 percent.Iraqi Shi'ite leaders are wary of the impact the Syrian conflict may have on their own country's Sunni, Shi'ite and Kurdish balance. Their worst-case scenario would be Assad's replacement by a hardline Salafi Sunni government.Ayman al-Zawahri, leader of al-Qaida, which shares the Salafi version of Islam, urged Muslims in Turkey, Iraq, Lebanon and Jordan to join Syrian rebels, in a video posted on Sunday.Al-Qaida in Iraq, though weakened by losses of key leaders is still a potent force. Local officials say insurgents are resurfacing in old strongholds now that American troops have left. Their pullout has also reduced intelligence capabilities."Arms dealers have been more active recently, especially when clashes intensified in Syria between the regime and opposition," said Hamid al-Hayes, head of the Anbar council, a tribal body whose government-backed Sahwa militia once helped turn the tide against al-Qaida affiliates in Iraq.