At first the smoke billowing from the national penitentiary in the Haitian capital seemed of no consequence.
On 1 December, US Secretary of State Colin Powell was visiting Haitian President Boniface Alexandre. The UN peacekeeping force in the capital, Port-au-Prince, was preoccupied with guarding the national palace where Powell's visit was taking place. But meanwhile, in the prison, something terrible was unfolding.
According to official reports, prisoners in a three-storey cell block called 'Titanic' had rioted, breaking free from their cells, setting fire to mattresses and brandishing water pipes as weapons. Prison guards called in a special police unit to help put down the uprising, and officials later said that seven prisoners had been killed and more than 40 detainees and guards wounded during the fracas.
But according to prisoners and others interviewed by The Observer, this is a woeful understatement. The government, they say, is concealing a savage bloodbath in which dozens of detainees were killed by police and guards.
The allegations are contested by officials but, if true, the killings at the penitentiary represent another black mark for Haiti's interim government, which has come under fire for allegedly perpetrating and tolerating human rights abuses ever since taking over last March from the ousted former president, Jean-Bertrand Aristide.
'I saw everything,' said Ted Nazaire, 24, a prisoner who was released two days after the riot and is now in hiding. 'It was a massacre. More than 60 were killed.'
Nazaire said police opened fire on the detainees, and then went from cell to cell, forcing prisoners into a passageway and methodically executing them.
He claims to have witnessed the killings while hiding under a staircase. When he was later found, he said, he was badly beaten by prison guards and warned not to talk about what he had seen. His family members complain that police harass them in their home nearly every day in their search for Nazaire, who at the moment walks with a limp, is covered with finger-length lesions and has a swollen left eye and a bump on his forehead.
Estimates made by prisoners at the number killed range from 40 to 110. 'I saw more than 30 dead people with my own eyes,' said Frantz Rubin, a detainee whose cell has a view into the passageway where prisoners allege many of the killings took place. 'We want justice.'
Prisoners and police say the riot was motivated by the decision to transfer some detainees to another penitentiary, combined with mounting frustration at the slow progress of their legal cases. Only 17 of around 1,100 prisoners at the national penitentiary have been convicted of a crime, and many detainees have not seen a judge.
Penitentiary warden Sony Marcellus dismissed the accusations made by Nazaire and the other prisoners as lies and exaggerations. 'The prisoners will never tell the truth,' he said. '[The guards] are trained to shoot in the air, not at prisoners. They would never fire on prisoners in this way.'
He pointed to an affidavit signed by a justice of the peace who had seen only seven bodies at the penitentiary the night of 1 December.
But Nazaire and the other prisoners are not alone in their testimonies. Two rights groups say that prison guards asking for anonymity have confirmed that the official death tally is an underestimate. And an ambulance driver who requested to remain anonymous said he transported more than 30 bodies in a Toyota Land Cruiser in three trips from the penitentiary to a dump site outside the city.
He added that there were two other vehicles also transporting bodies, although he refused to reveal the location of the site, saying he feared for his and his family's lives.
People who live and work in the streets surrounding the penitentiary said they heard heavy continuous gunfire lasting between two and three hours. A neighbour and a reporter at a nearby radio station, both with views of a catwalk that runs along the outer walls of the jail, said they saw police officers with machine-guns firing down into the building and at prisoners' cells.
But evidence that more than seven people were killed at the penitentiary has gone no further than the testimonies of prisoners and anonymous sources.
Jean Pierre Audain, Haiti's chief prosecutor, said he has ordered an investigation of the riot and its aftermath. But the details of this investigation are not clear.
Meanwhile, the penitentiary and its prisoners remain shrouded in secrecy. Since 1 December the authorities have barred visits from journalists, human rights observers, prisoners' lawyers and family members, all of whom were previously allowed to enter regularly.
Last week, at the Port-au-Prince general hospital, three prison guards stood over a wounded prisoner whose leg was manacled to a cot and prevented anyone from speaking to him.
Outside the penitentiary last Thursday, around 30 women waiting in the shade of the building's peeling concrete façade said they had still not seen their husbands and sons. Some have received written messages or assurances from the guards that their relatives are safe, but many are left to guess.
'I have my son inside. Yonel Pierre,' said a frail, white-haired woman as she waited to deliver a portion of rice and beans. 'Since 1 December, I've brought food for my son, but I haven't received any news from him. Before I used to get back the dirty dishes, but now I don't get anything.'
Her visits may be in vain. Among the seven dead confirmed by the justice of the peace is a police spokeswoman Gessy Coicou. The official death toll is now 10, as three prisoners wounded in the riot and its aftermath have died since 1 December. This list has not been made public.
And the guards have not told Mrs Pierre whether her son, who was in a cell on the second floor of the Titanic, is dead or alive.