The smell of raw sewage and food waste permeates the air in the entrance to Haiti's National Penitentiary in downtown Port-au-Prince.

Its source is the exposed pipe that visitors must walk over as a liquid mix slides through to the street.

A pat-down of even our heads from quiet security guards follows and then a large metal door swings open, revealing a courtyard on the other side.

In this world exclusive, CNN came to the prison hoping to speak to a certain group of inmates whom the government has refused to make available until now: Some of the 26 Colombians and two Haitian-Americans that investigators say entered Haitian President Jovenel Moise's bedroom in the early morning hours of July 7 and killed him in a hail of gunfire.

Haitian authorities call these men assassins. They call themselves innocent.

"We were useful idiots for someone else," one of the men told us. "But we did not commit this crime." More than five months detained after that deadly night, the men have not been formally charged.

CNN was allowed to enter the penitentiary after months of negotiation, with only paper and a pen, and told to wait in a wooden hut in the prison courtyard. Twenty minutes later, five Colombian men clearly not expecting our visit walked toward us in shorts, t-shirts and dark blue croc-style sandals, looking gaunt and unhealthy.

In an exclusive interview, these five are the first and only suspects in the assassination case to speak out publicly. They agreed to do so only if their identities were withheld, fearing for their own safety and that of their families.

Their message was consistent over an hour-long conversation in their native Spanish -- they are innocent, they have been tortured and they have been set-up.

Afraid to talk

All five men said they arrived in Haiti in June, about a month before the assassination that would upturn their lives and throw the country's political landscape into chaos.

All former Colombian soldiers, they told CNN they were hired as private security by a company called CTU.

Promised anywhere from $2,700-3,000 a month, they took on the job. According to the five men CNN spoke to and the wives of several others, they were never paid a dime.

CTU has not responded to CNN's prior requests for comment and it's unclear if the company even still exists.

"We were told that we were going to provide security for a Haiti presidential candidate," said one of the men. "We had no idea what was going to happen."

In Haiti, they were part of a group of more than two dozen Colombians who lived and worked together in a compound in the capital city Port-au-Prince, not that far from where then-President Moise lived.

In the dead of night on July 7, this group was loaded into a convoy that would rumble up Pelerin Road to the presidential compound.

The president would be fatally shot shortly afterward. His wife, First Lady Martine Moise, was severely injured in the gunfire as well.

CNN asked the five prisoners repeatedly for more details about the assassination, including what happened during the assassination, who was behind it, what their individual involvement specifically was and what they did in the hours after that killing.

They insisted they were not responsible for the president's death but declined to answer further questions or go into details about that fatal morning for two common reasons: First, that none currently have legal representation and second, that they fear for their lives.

"We are stuck in this prison," said one man. "We have to stay here. I will scream out loud all that I know when I can leave here but while we are here, we are terrified of reprisals."

"I am scared for what they might do to me but also for what they might do to my family [in Colombia]," said another man.

'They beat all of us'

Sometime after Moise was assassinated in the early morning hours, the five men interviewed by CNN left in that same convoy. Their vehicles were captured on cell phone video shot by several locals in the area.

But they didn't make it very far before they were boxed-in by Haitian security forces, they said. Forced out of their cars, they took shelter in a nearby empty building. Hours later, they fled out the back of the building and up a steep hill, making their way to the Taiwan embassy.

According to Taiwan's foreign ministry and a source in Haitian security forces, the group of Colombians forced their way inside, tying up two guards in the process. But Haitian law enforcement officers tracked them down, and they turned themselves in.

Once in custody, the beatings began, the prisoners allege.

One of the Colombians was stabbed multiple times by Haitian police while several others were pistol whipped over the head, they said. Others were beaten, with one attacked so brutally that his face would be disfigured by the blows, they recounted to CNN.

The men said before being transferred to the notorious National Penitentiary, they were held in an undisclosed location for more than three weeks.

"They held us somewhere else for 25 days, handcuffed in pairs. We went to the bathroom on the floor," said one prisoner.

The men said the beatings were continuous and brutal, and that they feared for their families' safety back home in Colombia.

"Do you know how hard it is when they show you a picture of your family on a cell phone?," asked one man, tears welling up in his eyes. "We had to do what they said."

And what they were asked to do, said each man, was sign their names to official statements they did not give and which were written in a language they could not read.

"I was sitting quietly, not saying a word and the officer was writing my statement for me," said one man. "He kept looking at me and writing more even though I hadn't said anything. They were writing and we were quiet."

He then signed a name to a document written in French, a language that he could not understand, he said.

All five men alleged that they had been forced to sign declarations under duress.

"The real people responsible for this are outside of the prison and we're stuck in here. We were cheated, framed, and scammed," said one man.

Haiti's National Police did not reply to CNN's request for comment. Asked about the allegations of torture in police custody, a Haitian federal government spokesperson said the government "has nothing to hide" pointing out that CNN had "full permission to visit the Colombians."

The same spokesperson denied that any official testimony was recorded without the Colombians' knowledge of what was being written.

"Based on credible information, they were provided translators so they understood what to sign or not," said the spokesman.

Little food, no legal representation

The five men have been held at Haiti's National Penitentiary since late summer.

The conditions in the prison are visibly horrific, with multiple men crowded into a single cell. Sanitation appeared to be an afterthought. Rats scampered across the grounds.

"Our lives are worth nothing in here," one of the Colombian prisoners told us.

The men say they receive one plate of rice per day, or sometimes corn. Each says they have lost more than 30 pounds. Some are noticeably losing their hair leaving patchy clumps on their heads, a clear sign of malnutrition.

"It's inhuman what is happening to us here," one of the men, in tears, said.

Haiti's leading human rights organization, The National Human Rights Defense Network (RNDDH), also describes general conditions in the prison as inhumane. "The prison doesn't have enough food, gas to cook and adequate access to care despite receiving more and more prisoners in the 12 months," they said in a report released last month.

"We fully respect human rights," said a Haitian federal government spokesperson. "We have no grudges against the Colombian prisoners."

The government did not respond to questions about why the men had not yet been formally charged.

But more than five months after the assassination, none of the men have legal representation -- a prerequisite to having their testimonies heard by a judge. They say the Haitian judicial system has only offered them junior lawyers with whom they could not communicate.

"They sent me some lawyer in his second semester who didn't speak Spanish," said one of the men. "I'm not going to trust my life with him."

According to a person close to the case, the lawyers provided to represent the men were not students, but rather apprentices. Before becoming practicing lawyers, law graduates must serve what is typically a two-year apprenticeship.

Though they are not fully qualified lawyers and have little experience, these apprentices are commonly appointed to represent those who cannot afford a private attorney, according to Brian Concannon, an expert with decades of experience working Haiti's legal system.

"So they are defending serious felony cases when they are not allowed to appear in a simple contract case [because they are not yet practicing attorneys]," said Concannon. "They have no budget for investigation and typically get no compensation for their time."

The men had hoped the Colombian government would provide them with some legal assistance, but that so far has not happened.

Haiti's government has also said the responsibility lies with Colombia now. "We hope government officials of Colombia provide lawyers to the prisoners so they can be examined by the judge [overseeing this case]," said a Haitian government spokesperson, adding that they cannot be officially questioned without an attorney present.

The Colombian federal government in Bogotá did not respond to CNN's request for comment, and the Colombian Embassy in Haiti referred our questions to the Foreign Ministry.

A public statement from late July said Colombian government representatives met with Colombian suspects with an attorney present. However, the men we spoke to said that none of the Colombians in the prison currently have legal representation.

Adding insult to injury, the men say, they have never received an explanation of the legal basis for their long detention.

"At no point has someone in [the legal process] looked me in the face and said, 'This is why you are here,'" said one of the men. "We obviously know why we're in here but there is no rule of law or due process here. Everyone should be innocent until proven guilty and we all have rights to legal representation."

The prisoners wrapped up the hour-long conversation with a message to the international community.

"Please find the love in your hearts to understand our situation and give us some benefit of the doubt," said one man. "The best thing that could happen is that this is brought to an international tribunal. When I am out of this country, I will tell the world everything I know." (CNN: Excludes headline)

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