For a brief moment, on the morning of Sept. 11, 2001, Teresa Garcia thought she'd seen a ghost.

She was in her office in midtown Manhattan, watching the news of the attacks on the World Trade Center, when he walked in.

"He was covered with dust. All white dust. And we couldn't even recognize him," Garcia says, recalling that day. "But he talked to my coworker and he said 'Esperanza.' And she said, 'Chino, is that you?' "

Garcia works at Asociacion Tepeyac de New York, a non-profit that assists mostly Latino immigrants with English language skills, legal aid and tax assistance.

The man who walked in, Chino, was an undocumented immigrant. Garcia is using only nickname to protect his identity. He had been heading over to start his shift at a restaurant at one of the towers, when the first plane hit. In shock, he made his way to Asociacion Tepeyac, to see Garcia and her colleague Esperanza Chacon.

"He came over to her (Esperanza)," Garcias says, "and he embraced her, and they started crying."

Little by little, dozens of workers started filing into Tepeyac's offices, looking for comfort among friends. But what stood out were those who were missing, their friends who worked as cooks and cleaners, at or near the World Trade Center.

The workers who'd gathered at Tepeyac started compiling a list, which in the next few days grew to 700 missing people. Almost all immigrants, many undocumented.

That list was important. In order to get financial or medical aid, New Yorkers or their families had to prove they worked at or near ground zero and that they were affected by the attack. Knowing who was there also would allow families to mourn, to bring closure.

For years, the people at Tepeyac and other families have been trying to prove the immigrants who worked at the World Trade Center existed. That effort has proved to be extremely challenging.

How do you prove a person, who deliberately had tried to stay hidden from the system, was real without the proper documentation?

Garcia and the others could see a bureaucratic nightmare beginning to unfold and they got to work. Tepeyac started sending folks to look through missing people's homes, she says, to look through their personal belongings, "to see if they had a passport, a birth certificate, if they sent money with names [on the order]. And it was real difficult, because people weren't using their real identities."

Friendships were built working at the Twin Towers

Sekou Siby understands the dilemma. He came to the United States in 1996, an undocumented immigrant fleeing political unrest in Cote D'Ivoire.

After 9/11 killed dozens of his friends, many whose families were undocumented, Sekou Siby became a labor right organizer.

Caption

After 9/11 killed dozens of his friends, many whose families were undocumented, Sekou Siby became a labor right organizer. / Jasmine Garsd/NPR

He worked as a deliveryman in the Bronx, subsisting solely on tips.

A few years later, he had secured a work permit as he sought asylum status. He says when his roommate got him a job as a prep cook at World Trade Center, it felt like a big break.

The WTC was the hub of global finance, a symbol of money and power. For hundreds of immigrants, it also was a place of stable, but low-wage employment. Siby's prep cook job came with free meals, though, and that supplemented food he couldn't otherwise afford.

A prep cook at the Windows On The World restaurant, on the 106th floor of the North Tower.

The work was grueling, especially for a former high school French teacher unaccustomed to that type of physical labor.

"It was a huge space," Siby says. "When we had a party of sometimes 2 or 3,000 people, you could spend two days just peeling onions. About 10, 15 lbs of carrots, potatoes to peel."

Sometimes, when he had time off, Siby would walk up to one of the restaurant's legendary, massive windows overlooking Manhattan, Brooklyn and New Jersey. "I remember leaning my back on that glass window, it felt safe and secure."

Down below, on the streets, Siby never felt safe. He was terrified of being denied asylum and sent back to Cote D'Ivoire. He says, up there in the restaurant, on top of the world, he perfected the art of being invisible: Don't ask for help, don't complain, don't draw attention.

"This is the reality of an immigrant. You have to be invisible in order to exist. Being out there, it's just exposing yourself. Especially when you are not solid," he says. "You can be picked up any day. It is important for you to be invisible. Never go to the police. You don't want to deal with any government entity."

All the workers in the towers understood this. Being immigrants brought camaraderie behind those kitchen doors. The Muslim workers bonded during Ramadan. There were playful wars over what music to play, which the Dominicans always seemed to win, he says.

And there were soccer games on weekends in Queens. It was after one of those games that Siby's friend, Moises Rivas, from Ecuador, asked to swap days. Siby agreed to work the Sunday shift, on Sept. 9th. In exchange, Rivas would take Tuesday, Sept. 11.

He remembers that morning. He got a desperate call from the wife of his roommate- the one who'd gotten him a job at Windows Of The World.

"'Your building is burning. Turn the TV on, a helicopter or a plane hit the building! I'm calling my husband, he's not picking up the phone. Can you help me?' " she asked him. Siby says he called over and over again. "I had two phone numbers for the kitchen, and they started ringing. And they kept on ringing until the building collapsed."

Siby spent the next few days running from one hospital to another throughout Manhattan, searching for his co-workers. As he took calls from their desperate families, he realized they were coming to him because so many were undocumented. They they weren't asking officials for help.

"You have the police asking for ID," Siby says, incredulously. "I mean, who in his right mind will go to the police with a fake ID?"

He still thinks of all people who are missing. And he remains haunted by guilt. He should have worked that day. Not his friend.

Convincing people who lived hidden to come forward proved difficult

The 9/11 Victim Compensation Fund made it clear that people could apply regardless of immigration status. This was easier said than done.

One of the most comprehensive reports written about undocumented immigrants who went missing during the 9/11 attacks, was put together by Alexandra Delano from the New School, and Benjamin Nienass at Monclair State University.

"This idea that somehow, in a moment of tragedy you can make the life of an undocumented migrant more public, and public services and federal relief services more accessible, that's just not possible," Nienass says. "Once you have been socially and politically isolated, it's extremely hard to trust public agencies again. It is also extremely hard to build the knowledge on how to proceed, how to access them."

Eventually, Tepeyac whittled its list of 700 or so missing people to 67. But Garcia says of that number, the families of only 12 of the missing would come forward and be able to prove the existence of their loved one so they could get some aid.

Some of the assistance came from churches, non-profits, and private donors.

At Greenfield Hill Congregational in Connecticut, Rev. Alida Ward says she remembers walking into the church office one mid-December morning in 2001.

"There was an envelope in my mailbox, and I opened it up ... and a check for a quarter million dollars fell out. There was a note that said: 'Please use this for all the people who aren't being reached,' " she says.

The church used the money to create grants for families.

The remains of more than 1,106 people from 9/11 have not been found.

The Mexican consulate alone estimates that 16 nationals died that day. There was only sufficient evidence for five to be acknowledged at the National Sept. 11 Memorial.

So much bureaucracy has left many families without closure

For many families of the missing immigrants, there is simply the desire for an acknowledgment.

Prof. Alexandra Délano from The New School says, families live in this limbo "when someone has disappeared, and there is no possibility of confirming that this occurred. That was very difficult for families to deal with."

In fact, she says the families often asked for a death certificate, "even if they didn't get compensation or any kind of support."

Teresa Garcia says she remains haunted by the dozens of undocumented workers she believes remain missing at the site of 9/11.

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Teresa Garcia says she remains haunted by the dozens of undocumented workers she believes remain missing at the site of 9/11. / Jasmine Garsd/NPR

Teresa Garcia, from Asociacion Tepeyac, says she, too, has struggled with a profound sense of loss. She visited the National September 11 Memorial & Museum as it was being built. She says "it was like ... like a big hole. That's how it felt. It's so difficult to accept that some of our people, they never existed. It was so painful."

Garcia says she has lost contact with most of the families of the missing and the survivors. Except for one person, Chino, the man who showed up at her office on the morning of 9/11, looking like an apparition, caked in white dust.

"He calls me, on 9/11. Every 9/11," she says.

She's expecting his call this Saturday. She'll ask him how life is in the suburbs in Connecticut, where he moved to after the attacks.

He'll tell her he has trouble breathing, and she'll urge him to go to the doctor- what if it's something he inhaled that day?

He'll respond the way he always does: whatever it is, he doesn't want to know. And she says she knows what he'll say next:

"Oh my God. I am so lucky to be alive."

But he doesn't like to talk about how it happened.

Or the invisible people they both tried so hard to find.

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