frightening headline out of syria. New concerns as the u.S. May have to intervene in the bloody civil war in that country. This morning, we're learning that syrian dictator, bashar al assad's forces... See More
frightening headline out of syria. New concerns as the u.S. May have to intervene in the bloody civil war in that country. This morning, we're learning that syrian dictator, bashar al assad's forces have done in recent days that's alarmed u.S. Officials and prompted a stern warning from president obama. And abc's martha raddatz is here with the details this morning. Good morning, martha. Reporter: Good morning, josh. This morning, a u.S. Official is confirming that over the weekend, the syrian military loaded elements of the deadly nerve gas, sarin, on to bombs on or near syrian airfields. There's 40 chemical weapons sites like this one. One drop of sarin can kil you within minutes. The theory is that the sarin bombs could be put on syrian warplanes to use against the opposition forces. There's no way to know for certain if that was the plan. But president obama was so concerned, he issued that strong warning on monday. And since then, there has been no activity at those airfields. And the syrian government insists it will not use chemical weapons. But that does not mean this threat has gone away. Opposition forces are gaining ground in syria's capital, putting more pressure on syria's unpredictable and vicious president. Josh? And as news becomes available, we'll have it for you. Martha, thank you for that.
This transcript has been automatically generated and may not be 100% accurate.