AKCAKALE, Turkey: Syrian rebels battled government forces near a Turkish border crossing on Tuesday and bullets flew into the northern neighbour that has backed the 18-month-old uprising against President Bashar al-Assad.

The revolt, which began as peaceful street protests cracked down on by Assad's military, has escalated into a civil war in which over 27,000 people have died. Daily death tolls now approach 200 and the last month was the bloodiest yet.

In another bid to stem the bloodshed, Iran's foreign minister proposed a new regional monitoring mission ahead of talks with President Bashar al-Assad in Damascus on Wednesday, Iranian state media said. Two previous missions have collapsed.

From the Turkish side of the crossing with Tel Abyad, a Reuters witness heard sporadic, heavy machinegun fire and saw an ambulance nearby. A Turkish official said stray bullets hit some houses in the town of Akcakale, wounding at least one person, a woman.

He said the rebels were trying to gain control of Tel Abyad, which was a major crossing for Turkish-Syrian commerce in peacetime, and which rebels were rumoured to have used for weapons smuggling in the past year.

It appeared to be the first attempt by insurgents to assert their grip over a border zone in al-Raqqa province, most of which has remained solidly pro-Assad.

Rebels hold two other crossings on the northern border with Turkey. A third border point would help strengthen their control in the north and put more pressure on the army as they battle for control of Syria's largest city Aleppo not far away.

Residents say only one town near the border has welcomed rebels in al-Raqqa province. The town held an anti-Assad protest on Tuesday, prompting government shelling, wounding several people, and fighting later erupted.

Parts of Syria's frontiers with Turkey, Lebanon and Iraq have become porous as the conflict spread. More than 200,000 refugees have poured into Turkey and Jordan to escape bombardment by pro-Assad forces in pursuit of rebels.

Shell fire has occasionally crashed over the borders, and the fighting has sometimes come so close that the armies of neighbouring states have gone on high alert.

Syria's second and third cities, Aleppo and Homs, have been shattered by fighting. With the army relying on fighter jets and helicopter gunships and the rebels on makeshift bombs, neighbourhoods in both cities have been levelled.

Damascus, once seen as an impregnable Assad stronghold, has also suffered near daily shelling and clashes on its outskirts.

At least five fighters and four soldiers died in the latest clashes on the capital's southern outskirts, the London-based Syrian Observatory or Human Rights said.

Security forces are trying to stamp out a rebel foothold in Damascus's southern and eastern suburbs.

Heavy army shelling battered rebellious towns in the southern Deraa region, fount of the uprising, and Idlib, in the north near the Turkish border. More than 60 people were killed nationwide before evening on Tuesday, the Observatory said.

IRAN PROPOSES NEW MONITORING MISSION

Iranian Foreign Minister Ali Akbar Salehi pitched his proposal for an observer force when a regional "contact group" met in Cairo on Monday, Iran's state news agency said. He said observers should come from the group's four member countries - Iran, Egypt, Saudi Arabia and Turkey.

Given mutual mistrust within the quartet, it was unclear whether Salehi's proposal had much prospect of success. The new grouping is an awkward combination of supporters and opponents of the uprising. Iran has stuck by Assad while Saudi Arabia, Egypt and Turkey have demanded the president step down.

"Salehi suggested the sending of observers from the four countries to monitor the cessation of violence, the conducting of dialogue, emphasising the need for a sense of integration and national unity and Syrian territory," IRNA news agency reported.

Two monitoring missions in Syria have already unravelled. The first, a regional Arab League group of observers, left in protest at a continued escalation of violence with little sign of political reform pledged by Assad. A United Nations mission pulled out most of its observers for similar reasons.

Violence has intensified and spread across this large, pivotal Arab country and more than 200,000 refugees have flooded into neighbouring states.

Iraq, which in August closed its border crossings, reopened them on Tuesday to allow in 100 Syrian refugees per day. But Iraq will refuse entry to young men, officials said, citing security reasons, as many young men are believed to be rebels.

REGIONAL RIVALRIES POSE OBSTACLE

Western officials and diplomats are sceptical that the new Middle East contact group that convened in Cairo could reach any deal to draw down the spiralling violence in Syria.

The four countries have differences with sectarian and strategic dimensions that seem insurmountable.

Saudi Arabia and Turkey are actively supporting Syrian rebels and are believed to be training them as well. Other Sunni Muslim countries in the region are also throwing their weight behind the mostly Sunni-led uprising in Syria.

Shi'ite Muslim power Iran has supported Assad, whose Alawite sect, an offshoot of Shi'ite Islam, has dominated the country for decades. Tehran has acknowledged having members of its security forces there, but only in an advisory role. Rebels say that Iranian forces are helping Assad militarily.

Underlining the inherent tensions, Saudi Arabia's foreign minister stayed away from the Cairo meeting of the contact group on Monday. Egyptian officials did not say why no one else came in his place.

International powers seem to be equally deadlocked along old Cold War lines, with Western powers backing the Syrian opposition, and Russia and China blocking any U.N.-mandated intervention aimed at dislodging Assad.

Iranian state media said that Salehi, who like Moscow and Beijing has called for an internal resolution without foreign interference, was to meet Assad in Damascus on Wednesday and propose ways to resolve the Syrian crisis.