Reporter: In The Line Of Fire

The Early Show, CBS News Early Show Co-Anchor Julie Chen, traveling with U.S. troops
CBS/The Early Show
With a chemical suit on and gas mask in hand, The Early Show co-anchor Julie Chen, filed the following report outside of a bunker at an undisclosed desert air base where she has been since 2:00 a.m. ET Thursday.

We were setting up to broadcast from here live. We were here about 2 1/2 hours, just finished an interview with the commanding officer of this secret air base, when his cell phone went off. He said he had to go; he said, "I'll be right there." Don't know whom he was talking to. He was calm the whole time. He assured us we were safe. Smiled, winked at me, said,"You're OK. You're in good hands; you'll be all right, Julie." And he walked off.

My crew and I continued to set up for the broadcast and about five minutes later, all of a sudden everyone started screaming,"Bunker, bunker, bunker." We just grabbed everything and ran towards the bunker. It was a three- to five-minute run from where we were setting up. Once we got in the bunker, we were told to get our chemical suits on, which is what I'm wearing right now.

All started putting on their gas masks. We had to basically cover every inch of skin that might be exposed. Hoods on, gas masks on, gloves on, boots that I still have on and will not take off.

We were all holed up in a bunker with about 100 marines. We were in there under alarm red, which means an air attack is imminent, or in progress. While we were in the bunker for 45 minutes, we heard two explosions. The military at this hour is not confirming whether or not that was a scud attack or artillery. They're not saying anything yet. But the marines are telling us better safe than sorry.

We stayed in there again for 45 minutes when all of a sudden we heard all clear. Everyone laughed, took off their gas masks, kind of breathed a sigh of relief. I have to say all the marines kept us calm, kept me calm the entire time. This is what they do. This is what they're trained to do.

About 10 minutes, maybe 10 minutes max, of having this gas mask off, of standing down, suddenly we heard the alarms go again. Everyone was screaming to get back in the bunker. Suit up again. Which they call "mach level." You have to have every inch of your skin covered and it was nerve-racking. We stayed in the bunker again for probably another 20 minutes.

Right now, we have been told to stand down but we have been told we have to keep these chemical suits on, our gas masks at our side the entire time. We're allowed to not wear the gloves. But we have to have them with us and to drink plenty of water.

We will report as soon as we can, but I know that the military wants us to get back in the bunker and get to a safe location as soon as possible.