Forces loyal to Syrian President Bashar al-Assad have fired Scud missiles at rebels trying to overthrow Syria's government, a senior US official said tonight.
Use of the missiles was seen as escalation in Mr Assad's attempt to retain power.
A US official confirmed a report that forces of President Bashar Assad have fired the missiles from the Damascus area into northern Syria.
He estimated that the number of Scuds fired was more than half a dozen.
The official said there was no indication that chemical weapons were on board the missiles.
Officials have said over the past week that they feared rebel advances were prompting Mr Assad to consider using chemical weapons.
In Brussels, a NATO official also said that a number of short-range ballistic missiles have been launched inside Syria this week.
"Allied intelligence, surveillance and reconnaissance assets have detected the launch of a number of unguided, short-range ballistic missiles inside Syria this week. ... Trajectory and distance traveled indicate they were Scud-type missiles," the NATO official said.
Speaking separately, US State Department spokeswoman Victoria Nuland, while not confirming the use of Scuds, said the United States has seen the use of incendiary barrel bombs in recent days.
"As the regime becomes more and more desperate, we see it resorting to increased lethality and more vicious weapons moving forward," she told a State Department briefing.
Reuters and PA