Nightly News | April 25, 2013
>>> another big story we are following tonight. the u.s. intelligence community now believes chemical weapons have been used in syria . president obama has previously said that would be crossing a red line for the assad regime. our pentagon correspondent jim miklaszewski is traveling with defense secretary hagel in the middle east where he learned more about this today.
>> reporter: after two years of syria 's bloody civil war , the obama administration inched ever so slightly today toward u.s. military intervention. secretary hagel speaking for the white house accusing syria of using chemical weapons .
>> the u.s. intelligence community assesses with some degree of varying confidence if the syrian regime has used chemical weapons on a small scale in syria .
>> reporter: it's believed traces of saran were with found in blood samples taken from victims of an attack last month in aleppo. president obama has warned syria 's use of chemical weapons would be what he's called a game-changer that could trigger military action .
>> that's a red line for us. there would be enormous consequences.
>> reporter: the administration has never spelled out what those consequences would be. they stressed today the evidence so far is not strong enough.
>> we still have some uncertainties about what was used, what kind of chemical was used, where it was used, who used it.
>> reporter: but on capitol hill today republicans demanded military intervention .
>> i think it's pretty obvious that red line has been crossed.
>> reporter: u.s. military options could include cruise missile strikes against regime targets. as ground forces seize syria 's chemical weapons . but could such a high risk ground mission succeed?
>> not as i sit here today, simply because they have been moving it and the number of sites is quite numerous.
>> reporter: while administration officials insist any u.s. military option would be a last resort. those same officials compare the current situation in syria to iraq where the u.s. went to war over weapons of mass destruction that didn't exist. as one senior official put it, we have seen that bad movie before. brian?
>> all right. jim miklaszewski traveling with the defense secretary in