* Base is nearest to Damascus reported to have fallen
* Heavy bombardment to try to stop base falling - activists
* Some Islamist leaders reject newly formed opposition group
* Turkey may ask NATO for air defence missiles within days
By Oliver Holmes and Khaled Yacoub Oweis
BEIRUT/AMMAN, Nov 19 (Reuters) - Syrian rebels said they had seized the headquarters of an army battalion near the southern gate of Damascus on Monday, the nearest military base to the capital reported to have fallen to opposition fighters in a 20-month revolt.
Activists said the Syrian army had attacked southern districts of Damascus with shelling and rocket fire all day to try to stop the rebels seizing the base, in some of the heaviest bombardment of the capital.
“Multiple rocket launchers are just making huge, random destruction,” said Rami al-Sayyed of the Syrian Media Centre, an opposition organisation monitoring the crackdown by President Bashar al-Assad’s forces.
The Islamist rebel groups Ansar al-Islam and Jund Allah Brigades said in a statement that they had taken the Air Defence Battalion base near Hajar al-Aswad after four days of fighting.
The district had been home to thousands of refugees from the Israeli-occupied Golan Heights. These were at the forefront of the movement against Assad’s autocratic rule at the beginning of a revolt that has now turned into a civil war, in which activists say 38,000 people have been killed.
Activists said all the residents had fled under the bombardment.
Video footage showed rebels walking through the site, past destroyed anti-aircraft guns, and one commander saying on a walkie-talkie: “We have completely seized the compound.”
Louay al-Dimashki, an opposition activist who said he had documented the fall of the base on video, said the rebels had targeted the compound with mortars then attacked in small groups, killing 14 loyalist troops and taking 35 prisoner.
“The fighters are taking whatever ammunition and weapons they can. They cannot hold on to the base because the regime will hit them from the air,” Dimashki said by phone.
Independent verification of the reports was not possible because Syria severely restricts the access of foreign media.
Rebels have captured several army positions in outlying regions in the last week, including a Special Forces base near the northern city of Aleppo and a small military airport in the east, on the border with Iraq.
Inside Damascus, a roadside bomb hit a minibus along a route used by security forces and pro-government media, activists said. The opposition Syrian Observatory for Human Rights said three people had been killed and at least 10 wounded.
Under pressure from foreign states keen to promote a viable and responsible alternative to Assad, Syria’s fractious opposition formed a broader coalition group last week, led by moderate Sunni Muslim preacher Mouaz Alkhatib.
The Syrian National Coalition was promptly recognised by France as the sole legitimate representative of the Syrian people.
EU foreign ministers said on Monday they considered the group to be “legitimate representatives” of the Syrian people, stopping just short of the full recognition offered by France.
A group of Islamist fighters in Syria’s Aleppo province, many of whom are well-known members of powerful rebel units in the area, said on Monday they rejected the umbrella group and planned to establish an Islamic state in Syria.
Members of Islamist groups listed in a YouTube video as supporters of the plan told Reuters they had nothing to do with the announcement, though they acknowledged that some members of their groups had appeared in the video.
This could suggest cracks in Islamist rebel ranks over how to respond to growing efforts to unify rebel groups and potentially sideline more radical Islamist elements.
The expanding conflict has threatened to suck in Syria’s neighbours, especially Turkey in the north.
Syrian mortar rounds have fallen in Turkey, Lebanon and Israel as rebels hug the borders looking for safety, and Turkey’s army is stationing soldiers in recently dug trenches along the border.
Germany said Turkey was expected to formally request, perhaps within days, that NATO Patriot missiles be placed on its border to defend against Syrian attacks.
“There have been informal talks on a request like this in the past few days,” German Defence Minister Thomas de Maiziere said in Brussels on the sidelines of an EU defence ministers’ meeting.
Only Germany, the Netherlands and the United States have the appropriate Patriot missile system available.
De Maiziere said Berlin would study a Turkish request “with solidarity” and if Germany sent Patriot missiles to the Turkish border, German soldiers would accompany them.
A Turkish government official said Ankara was still consulting with NATO.
President Abdullah Gul told a press conference that Turkey was concerned about Soviet-era chemical weapons in Syria.
“In this context, there will always be contingency planning in a NATO country neighbouring Syria,” he said.
NATO has deployed Patriot surface-to-air missiles to Turkey twice before, in 1991 and 2003, during both Gulf Wars.
Any NATO-supplied missiles would not be for creating a no-fly zone in Syria and, although Turkey could count on “allied solidarity”, the missiles would be purely for defence, NATO Secretary General Anders Fogh Rasmussen said in Brussels.
Syrian rebels, despite seizing swathes of land, are almost defenceless against Syria’s air force and have called for an internationally enforced no-fly zone, a measure that helped Libyan rebels overthrow Muammar Gaddafi last year.
A Reuters cameraman on the Turkish border said hundreds of families had fled the Syrian town of Ras al-Ain and were gathering at a border gate after clashes between rebels and Kurdish separatists who are wary of both rebels and the government.