Syria strike prospect puts Damascus on edge as U.N. inspectors wrap up search for chemical weapons evidence

(CBS News) DAMASCUS - The United Nations weapons inspectors in Syria began their last day in the country Friday with a couple false starts, as anxiety gripped residents in the sprawling ancient city amid strong signals that the U.S. was preparing to launch strikes in the country, and the still-looming possibility of chemical weapons attacks.

CBS News correspondent Elizabeth Palmer reported that the team of 20 scientists and other U.N. workers left their Damascus hotel apparently hoping to revisit the suburbs where an alleged widespread chemical weapons attack left hundreds dead on Aug. 21. They've been into the area three times already this week.

They turned back in just minutes, however, possibly because the regime of President Bashar Assad was continuing to shell the eastern Ghouta suburbs. Palmer reported hearing artillery fire as she reported live on "CBS This Morning" Friday.

"It's been going on all morning," said Palmer.

Instead of making it into the suburbs, CBS News followed the inspectors to a Damascus military hospital, where they were to meet and interview six Syrian soldiers who also allegedly suffered from the effects of chemical agents of some sort upon entering into Ghouta.

Palmer reported that the men could have been manning roadblocks around the Ghouta suburbs when the attack occurred last week, or they could have been members of the Syrian army unit that, according to the government, discovered a large stockpile of chemical weapons belonging to rebel fighters in a tunnel in the area after the incident.

The facts of the Aug. 21 strike -- at least the facts of what chemical agent was used and how it was delivered -- won't be clear at least until the U.N. inspectors release their report. Friday was to be their last day collecting samples and interviewing people, and they were to leave the country on Saturday.

Where's the evidence Assad used chemical weapons?

U.N. Secretary-General Ban Ki-moon has said there will be a preliminary report soon, but a really specific one -- one that examines any traces of chemicals they found for markers that might even tell us who made them -- Palmer reported that those details could take days, or even weeks.

Meanwhile, Palmer, who has visited Damascus to cover the current crisis on numerous occasions and who had traveled to the city previously, said Friday it was a "very, very tense place."

"In the last year as the violence escalated, people got used to an awful lot," said Palmer. "The shelling that I was just talking about, mortars falling here and there, car bombs, but there's never been trepidation like there is right now."

Palmer explained that under the dual threat of another possible chemical weapons attack, and the very real threat of looming U.S. military strikes, even battle-weary Damascenes feel vulnerable.

"Nobody knows where the missiles are going to fall," said Palmer.