Upon Turkey's request, NATO decided in December to deploy six Patriot missile batteries close to the Syrian border. In October, Syrian artillery shells hit the Turkish town of Akcakale, killing five people.

"The battery, provided by the Netherlands, will help to protect the city and people of Adana (southern Turkey) against missile threats," read a statement on the NATO website.

NATO should deploy the other five batteries soon. Syria and Russia have criticized the weapons, which Turkey and NATO have stressed have a purely defensive function. Patriot missiles can take out cruise and ballistic missiles - as well as aircraft.

In Iran, one of Syrian President Bashar Assad's few remaining allies, a government official criticized any foreign involvement in the conflict.

"A military attack against Syria would also be an attack against Iran," said Ali Akbar Velayati, an aide to Supreme Leader Ayatollah Ali Khamenei, according to the Mehr news agency. "Syria is, in the region, part of a golden ring of resistance. For this reason, an attack on Syria would be considered an attack on Iran and Iran's allies."

Jailbreak in Iblib

Rebels freed more than 100 inmates at a major prison on Saturday, according to the British-based Syrian Observatory for Human Rights, which also said that 10 insurgents were killed in the jailbreak. The Observatory posted a video purporting to show the prisoners released in Idlib.

Media have reported continued heavy fighting near the prison. Al-Dunia television reported that army reinforcements have been sent in and that all communications with the facility have been cut off.

Activists in Damascus reported a car bomb blast in the al-Zahira neighborhood, but could not give a count on casualties, as troops had immediately cordoned off the area.

State television reported that troops raided several rebel-held regions near the capital and uncovered at least three tunnels used by opposition fighters to smuggle weapons. The state-run Syrian News Agency reported that tunnels were discovered near Daraya, south of the capital.

Troops have tried to capture Daraya for weeks, but have faced strong resistance. Daraya's proximity to a major military base means it has strategic significance for both sides.

In other news, Britain pledged a multimillion-dollar aid package to help Syrian civilians, nearly half of which would be channeled through agencies in Jordan, where a record 6,400 refugees arrived on Friday. The UN, which recently commissioned a study that put the 22-month conflict's death toll at 60,000 people, estimates the number of refugees in neighboring countries will double to 1.1 million by June if the civil war continues.

mkg/msh (AFP, dpa)