Nicole Still, TIME.com Senior Producer

As

my Manhattan-bound W train packed with rush-hour commuters emerged from the underground and burst into the sunlight on the Manhattan Bridge Tuesday morning, the familiar New York City skyline was gone, made invisible by a thick canopy of jet-black smoke.

Terrified at the sight, confused commuters pressed their faces against the train’s windows, climbing over one another to get a better view.

"Fire! The World Trade Center is on fire!" a young man in a pinstriped suit exclaimed.

Abandoning my morning copy of the New York Daily News, I pushed past a young man on a cell phone, craning my neck to get a better view.

To my utter disbelief, I could see smoke and flames devouring the top third of the north tower. The bitter smell of smoke burned in my nose.

Down the East River, I could see emergency vehicles racing across the Brooklyn Bridge towards the heart of New York City’s financial district.

Suddenly the train came to a screeching halt in the middle of the bridge.

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"The World Trade Center is on fire," the gravelly-voiced conductor said over the intercom. "All service to Cortlandt Street has been suspended. All persons are advised to stay out of the area. I repeat. Do not go near the World Trade Center."

Young men and women frantically dialed cell phones. A woman with raven black hair, dark sunglasses and a Gucci bag burst into tears.

My son, a blonde woman who looked to be in her 50s said in a choked whisper to the young girl sitting next to her, my oldest son works in that building.

As we all gaped and tried to process what we were witnessing, the unthinkable happened.

Like a scene in a Jerry Bruckheimer film, a big black foreboding jet came from out of nowhere and crashed into the south tower.

Everyone on the train gasped. One woman screamed. The passengers who could not see over the wall of people pressed against the windows, frantically yelled, "What happened? What happened?"

Speechless, I could not form the words to explain what I had just witnessed.

A million thoughts raced through my mind. What was happening? Could it be terrorists? I remembered from a few years ago, the widely publicized bomb threats made against the World Trade Center. I thought of the Oklahoma City bombing. Could it be terrorists? Were they Americans? How many people were killed?

I did not have a watch, but I knew it was roughly 9 a.m. Some 50,000 people work in those buildings. How many of them had just sat down their computer, turned it on and were dialing to check their voice mail? I breathed a sigh of relief that I knew no one who worked in that building and quietly said a series of "Hail Marys" under my breath.

As the train resumed and slowly crept closer to Manhattan, passengers on the train talked excitedly to one another, while others sat silence and a few closed their eyes and folded their hands in prayer.

"This is like a movie. This is like a movie," a middle-aged woman with red hair kept saying to her friends. "Who could do this?"

Finally, the train sunk back into the underground on the Manhattan Bank of the river and the smoke and flames disappeared from sight.

The train lurched forward and the conductor came on again.

"Due to the explosions and fires at the World Trade Center, we are experiencing extensive delays as trains on all lines are rerouted," the conductor said. "From the train crew we ask that you say a prayer for anyone at the World Trade Center. Please say a prayer."

For the first time, the train became gravely silent. The woman with the dark sunglasses and Gucci bag continued to weep quietly.

I sunk down into an empty seat. My heart was racing, and I closed my eyes.