NEW YORK >> Bryant Neal Vinas, a convicted terrorist from Long Island, showed up recently for dinner at Katz’s Delicatessen on the Lower East Side in oversize glasses with black rims, a thin attempt to alter his appearance.

After he was released from federal prison last year, Vinas assumed he would have no need for a disguise. He thought he was going into witness protection, with a home far away and a new identity, after he helped the U.S. government battle al-Qaida as one of the most important cooperators in the government’s fight against terrorism.

Captured in 2008 after training for months at Qaida camps, Vinas quickly turned on his fellow jihadis and began helping U.S. investigators dismantle the group. Even the federal judge who sentenced him described his cooperation as “remarkable.”

“I helped them kill my friends,” Vinas explained while eating pastrami on a hoagie roll with mayonnaise, his choice of condiment drawing a weird look from his lawyer and the waiter. He added, “If that doesn’t show how you’re willing to turn your life around, I don’t know what will.”

But the government decided against giving him protection, and Vinas, 35, has found himself unexpectedly back in New York, where he was raised and converted to Islam more than a decade ago. The FBI and the Justice Department declined to comment, but a senior government official said there were concerns about whether Vinas would adapt to the program and potential conflicts with law enforcement officials who administer the witness protection program.

Nonetheless, the decision could affect future government cases as defense lawyers weigh whether to help prosecutors. The FBI and federal prosecutors have long relied on informants to build cases against mob bosses, crooked Wall Street traders and drug dealers, and current and former law enforcement officials questioned whether potential cooperators would decline to help the government without a guarantee of safety in return.

“How often do you get an American who went into al-Qaida?” asked Jack Cloonan, a former FBI agent who investigated the group. “I would think you would want to do everything you could for him. If I were the agent, I would be hard-pressed to accept this.”

In a series of interviews, his first since being freed, Vinas gave an unusually revealing look at life inside al-Qaida. He spoke of a training camp, where he slept in flea-ridden sleeping bags but befriended other young men from around the world, and gained access to Qaida leaders, who discussed with him the most effective ways to cause mass destruction inside the United States. He suggested blowing up the Long Island Rail Road, or a Walmart.

He traveled to Lahore, Pakistan, in 2007 and eventually linked up with militants who provided training and took him to Afghanistan. Six months later, Vinas was living at a safe house in Waziristan, a tribal area in northwest Pakistan, with Qaida recruits from Egypt, Kuwait, Turkey and Saudi Arabia.

By March 2008, Vinas had begun basic training at a Qaida camp in northwest Pakistan. The living arrangements were primitive; trainees had to share the flea-infested sleeping bags. The food — rice, potato stew and boiled roots — gave him diarrhea and dysentery.

He met many Qaida leaders, including Saleh al-Somali, the chief of external operations, who planned an attack on New York’s subways that the FBI thwarted.

Pakistani authorities arrested Vinas in October 2008 in the Hayatabad neighborhood of Peshawar, where he had traveled to find a wife. The Pakistanis interrogated him, he said, and notified the U.S. government he had been caught. Vinas recalled thinking that he would be sent to the U.S. military prison at Guantánamo Bay, Cuba.

Instead, he was flown to Bagram Air Base in Afghanistan and then to New York to be prosecuted. “It was a long trip,” Vinas said, and members of the FBI-led Joint Terrorism Task Force took him to Katz’s after his arrest.

“A pastrami sandwich can really soften a hard heart,” Vinas said.

He immediately started providing information to the FBI and pleaded guilty in 2009 to federal terrorism charges.

He was later transferred to a federal prison in Otisville, and put in the witness security program inside its walls, according to former law enforcement officials. He had company: gang members, mobsters and another valuable FBI informant, Ahmed Abdulkadir Warsame, a Somali terrorist captured in international waters near Yemen in 2011.

Vinas spent eight years at Otisville.

Federal prosecutors as well as the FBI agents who handled the case pushed hard for witness protection, said Steve Zissou, Vinas’ lawyer, who believes Vinas remains in danger.

“That’s not what we do to people who help the United States,” he said. “Vinas paid his dues. At the minimum, he should be given an opportunity to rebuild his life and be safe and secure.”

“He never hurt anybody,” Zissou continued.

But one day before he was released, Vinas learned he would not be granted protection, angering the judge and Zissou. The Justice Department’s Office of Enforcement Operations, which approves or denies program applications, conducted a review and turned down Vinas, the senior government official said. A psychologist who examined Vinas during his final days in prison said he could be a possible threat to the people protecting him. The psychological evaluation caught everyone off guard, including the judge and Zissou.

Zissou dismissed the assessment.

“He’s not a threat to anybody,” Zissou said. Another psychologist evaluated Vinas after his release and said he was not a danger, but the Office of Enforcement Operations did not change its decision.

The FBI put him in an extended-stay hotel in New York. Farbod Azad, the FBI agent on his case, once brought him Fruity Pebbles and milk. Vinas thought that was a nice gesture, but then Azad said the FBI was done paying for the room.

Another government agency paid for another month, Zissou said, and then Vinas was sent to what is known as a three-quarters house in New York. He wears an ankle monitor and has a curfew.

Vinas is now on food stamps and Medicaid. He does odd jobs for his lawyer and has had little luck finding a job. He applied to Uber Eats but never heard back. He considered washing windows, but the union said it was not accepting applications.

Vinas realizes he cannot escape what he did. He is still hopeful about his future, but he knows he will not be living anonymously. Perhaps what happened is a blessing.

“I don’t have to hide anymore,” he said. “And I am not going to live in fear.”

© 2018 The New York Times Company