Syria military 'continuing to fire Scud-type missiles'
Nato Secretary General Anders Fogh Rasmussen says Syrian government forces are continuing to fire short-range ballistic missiles at rebel fighters.
A Nato source told the Reuters news agency that surveillance had detected multiple launches of "Scud-type missiles" on Thursday morning.
Mr Rasmussen said it was the "act of a desperate regime approaching collapse".
Last week, Nato and the US said more than six missiles had been fired from the Damascus area into northern Syria.
However, the Syrian foreign ministry strongly denied using such weapons.
The military is believed to have access to a range of artillery rockets and medium-range missiles, some capable of carrying chemical weapons.
These include the Soviet-designed SS-21 Scarab and Scud-B missiles.
'Need to protect Turkey'
Speaking to reporters in Brussels on Friday, Mr Rasmussen confirmed Nato and its allies had detected new launches of Scud-type missiles.
"We strongly regret that act," he said. "I consider it an act of a desperate regime approaching collapse."
"The fact that such missiles are used in Syria emphasises the need for effective defence and protection of our ally Turkey," he added, referring to Nato's decision to deploy several Patriot missile batteries along the country's southern border with Syria.
On Thursday evening, US officials also said forces loyal to President Bashar al-Assad had resumed firing ballistic missiles against rebel positions in recent days.
They said there was no indication that the missiles were armed with chemical weapons and had no information on any casualties, the New York Times reported.
Contacts inside Syria told the paper that one attack had taken place on Thursday near Maara, a town in a rebel-held area north of Aleppo, near Turkey. The missile reportedly missed its target and no-one was hurt.
'War of attrition'
On Friday, rebels attacked an air defence base protecting a military industrial compound in the northern town of al-Safira, just south of Aleppo, but were pushed back by soldiers, the UK-based Syrian Observatory for Human Rights said.
Rebels have accused the government of using civilian aircraft to transport troops and weapons to the northern city, many of whose road links they have cut off.
Meanwhile, speaking after his talks with EU leaders in Brussels, Russia's President Vladimir Putin insisted it was not "a defender of the current Syrian leadership".
He said Moscow would continue to "pursue public order in Syria" and looked forward to the establishment of "democratic regime".
The Dutch government confirmed it was supplying activists in Syria with equipment to record evidence of human rights violations. It will also help fund experts to analyse the films and photographs they collect, in preparation for any further trials.
It comes a day after the UN Commission of Inquiry on Syria noted in a new report that human rights violations continued unabated.
"The war of attrition that is being fought in Syria has brought immeasurable destruction and human suffering to the civilian population. As the conflict drags on, the parties have become ever more violent and unpredictable, which has led to their conduct increasingly being in breach of international law," it said.
The Syrian Observatory for Human Rights says more than 44,000 people have been killed in the past 21 months, including nearly 31,000 civilians.