By Khaled Yacoub Oweis
AMMAN (Reuters) - Fighting flared on Thursday between Syrian Sunni rebels and foreign militias near a main Shi'ite shrine on the southern edge of Damascus, opposition activists said, in an increasingly internationalized conflict deepening Middle East sectarian faultlines.
Heavy clashes were reported as rebels fighting to overthrow President Bashar al-Assad, whose Alawite sect is an offshoot of Shi'ite Islam, attacked Lebanese Hezbollah and Iraqi Shi'ite militia based in the Saida Zainab suburb of Damascus with mortar bombs and automatic weapons, the sources said.
Saida Zainab is named after a blue tiled and mirror decorated shrine in the center of the district dedicated to the granddaughter of the Prophet. Zainab was also the daughter of Caliph Ali, an especially revered figure in Shi'ite Islam who advocated tolerance.
Any damage to the shrine would inflame religious passions among Shi'ite communities worldwide and further polarize the various Middle East powers involved in the Syrian conflict. Before the revolt against Assad family rule, the shrine drew hundreds of thousands of pilgrims a year. Notables from Iran and Iraq are buried in its grounds.
A rebel commander described the attack as a counter-offensive to relieve pressure on the nearby rebel suburbs of al-Thiabiya and al-Boueida, as well as al-Husseiniya Palestinian refugee camp, where rebel brigades are trying to hold off an advance by the Shi'ite militias.
"We have lost several neighborhoods in the last couple of days. The aim of this offensive is to force the regime and his allies to retreat," commander Abu Abdelrahman of the Islamist al-Sahaba Brigades told Reuters from southern Damascus.
He said while the Syrian army has been providing heavy firepower against rebels, most of the pro-Assad forces doing the urban fighting in and around Saida Zainab and nearby districts are comprised of Hezbollah, Iraqi fighters as well as local paramilitary from Syria's small Shi'ite community.
Opposition Activist Rami al-Sayyed said the rebels deployed on Sunday in streets leading to a roundabout only a few hundred meters (yards) north of the shrine, where four Shi'ite militia were reported killed, he said, adding that several rebels were also killed in the region.
"There is stiff resistance. The objective is not to take the shrine but to force Hezbollah and its allies to retreat from the nearby districts," he said.
ARMY ROCKET BARRAGES
Sayyed said rebels and civilians were trapped in the besieged suburb of Thiabiya, situated near Saida Zainab, with Syrian army rocket barrages hitting the district.
"A first-aid worker managed to literally crawl out of Thiabiya today. He said there were bodies in the streets and that the shelling is too heavy to pick them up."
The 2-1/2-year-old war has killed more than 100,000 people and forced millions from their homes into sprawling refugee camps in neighboring countries.
It began with peaceful demonstrations against four decades of iron rule by the Assad family. With Shi'ite Iran and Sunni heavyweight Saudi Arabia backing opposing sides in the conflict and Russia blocking Western efforts to force Assad aside, there is little sign of an end to the bloodshed.
Regional security officials say fighters from Iraq, Iran and Yemen and Hezbollah are present in Syria supporting Assad, as well as foreign jihadists and Syrian expatriates on the side of the rebels.
Total number of foreign fighters on both sides runs in the tens of thousands, they said.
The Iraqi and Lebanese militia backed by Syrian army tanks and fighter jets overran on Wednesday Sheikh Omar, another southern suburb near Saida Zainab, putting pressure on several Islamist rebel brigades trying to hold onto strategic outskirts of the capital.
The deployment of the Iraqi and Lebanese militia has been vital in preventing all southern approaches to Damascus from falling into rebel hands, according to opposition sources and the regional security officials.
(Editing by Cynthia Osterman)