JEFFREY BROWN: The Syrians insisted today that they have not used chemical weapons. President Obama issued new warnings, while saying the U.S. and the world continue to seek conclusive evidence. All the while, the civil war in Syria raged on.
Explosions and heavy fighting rocked Damascus today, as government forces pressed an offensive to retake parts of the Syrian capital from rebels. At the same time, the war of words over chemical weapons escalated. Syrian government officials denied U.S. claims made yesterday. White House letters to senators said, "U.S. intelligence assesses with varying degrees of confidence that the Syrian regime has used chemical weapons on a small scale, specifically sarin."
The disclosure put new pressure on President Obama to take action. He met today with the visiting king of Jordan and said the findings are preliminary.
PRESIDENT BARACK OBAMA: We're going to be consulting with our partners in the region, as well as the international community and the United Nations, to make sure that we are investigating this as effectively and as quick -- as quickly as we can. It's obviously horrific, as it is when mortars are being fired on civilians and people are being indiscriminately killed. To use potential weapons of mass destruction on civilian populations, that is going to be a game changer.
JEFFREY BROWN: The president has also said any use of chemical weapons would cross a -- quote -- "red line."
And on Thursday, Republican Sen. John McCain said, it's been crossed.
SEN. JOHN MCCAIN, R-Ariz.: The president of the United States has now told us that they used chemical weapons. Those stocks of chemical weapons, some of which are in disputed areas, must be secured, and we must give the opposition the capability to drive out Bashar Assad once and for all.
JEFFREY BROWN: But other lawmakers today were more cautious. Democratic Congressman Dutch Ruppersberger of Maryland attended a closed briefing on the matter.
REP. DUTCH RUPPERSBERGER, D-Md.: We feel that there has been some chemical weapons that have been used, but we're still investigating who did it, where it's coming from. And right now, we're just in an evaluation stage. I don't think we, just as the United States, want to go into another war.
JEFFREY BROWN: A spokesman for the Syrian opposition welcomed the administration's findings and President Obama's promise of further investigation.
KHALID SALEH, Syrian National Coalition: The positions that the U.S. and U.K. took in the last couple of days are very advanced and we welcome them. We will invite investigators. We will cooperate with investigators. And we are certain that the evidence will show that the Syrian regime actually used those chemical weapons against innocent civilians.
JEFFREY BROWN: It was unclear how long further investigation might take. The president said today, "We have to make these assessments deliberately."