The aim of the killers is simple. By creating an atmosphere of terror they want to ensure that President Jean-Bertrand Aristide, ousted by a military coup two years ago, does not return or will come back with no real power. President Bill Clinton fears they may be right and is sending 700 American troops under the United Nations flag during the next week to ensure the transition to civilian rule.
In theory the transition has already begun. A civilian cabinet has been appointed. General Raoul Cedras, the army commander, and Colonel Michel Francois, the head of the Port-au-Prince police, who together led the 1991 coup in which 1,500 died, are to resign or be transferred. Both should get immunity under an amnesty. On 30 October President Aristide, 40, the Catholic priest elected with 67 per cent of the vote in 1990, returns from exile.
All this was agreed by both sides, under intense pressure from the United States, in New York on 3 July under the so-called Governor's Island agreement. But the spirit of compromise has been slow to show itself in Haiti, where the accord has led to a wave of killings and disappearances. Any sign of overt support for President Aristide is savagely punished. When a pro-Aristide poster is pasted to a wall, soldiers make passers-by tear it down and eat the paper, piece by piece.
Three weeks ago one spectacular killing made US and UN officials fear the agreement was on the verge of unravelling. On 11 September Antoine Izmery, a businessman and a leading supporter of President Aristide, attended a church service in the capital. Surrounded by foreign diplomats, he probably thought he was safe. As the service got under way, he was grabbed by men planted in the congregation, some of whom were later identified as being associated with the Haitian police.
They dragged Izmery into the street and shot him. Dante Caputo, the normally urbane head of the UN mission who negotiated Fr Aristide's return, reacted by calling Col Francois a 'killer'. Politically active Haitians were terrified, as the killers presumably intended. 'The Izmery assassination has worked in that there is no open organisation of Aristide's supporters,' says Ian Martin, head of the human rights section of the UN observer team.
Ordinary Haitians are frightened. Fear of the death squads sends them home at 9pm, leaving the streets of Port-au-Prince - once teeming with people late into the night - empty and menacing. But the brazenness of the Izmery execution may have been a miscalculation, since it forced the UN Security Council to respond. It is sending - nominally to provide technical assistance - 700 US troops and 550 French and Canadian police to Haiti.
Col Francois, if he was behind the killing of Izmery, might have done better to avoid a spectacular execution that humiliated the US and UN. President Clinton has never been enthusiastic about becoming involved in Haitian affairs, but, after setbacks in Bosnia and Somalia, he cannot afford a third debacle in Haiti. Failure here might also lead to a fresh and politically damaging exodus of Haitian refugees to Florida.
Gen Cedras, Col Francois and their allies may have agreed to the return of President Aristide because they never intended to surrender the substance of power. Perhaps they thought they could keep him a virtual prisoner in the presidential palace. If so, they may now be having second thoughts.
For the moment at least there are two governments in Port-au- Prince with bizarre and often bloody consequences. In theory there is a pro-Aristide Prime Minister, Robert Malval, the amicable owner of a large printing business, and his Cabinet, but since Izmery's death many Cabinet members have found good reason for extended foreign trips.
A visit to the Information and Culture Ministry, important because it controls television and radio, does not increase confidence in the authority of the new constitutional government. The Minister is Herve Dennis, a distinguished playwright, who has chosen this moment to produce a play in France. Given that the two soldiers armed with sub-machine guns, who loll in the chairs at the main door of his ministry, answer to Gen Cedras, his discretion is understandable.
Government employees certainly know who is in charge. A secretary in the entrance lobby of the ministry, asked what she thought of Aristide, looked frightened and closed the door, before placing her hand over her heart and saying: 'What we really think of Aristide we must keep here because if we speak . . .' She then performed a little pantomime, slapping her face and kicking out, to show she would be beaten.
Evans Paul, the mayor of Port- au-Prince, elected before the coup, did try to take back his office in City Hall. Ignoring broadcast warnings that he would be turned into tassot - a fried meat dish - he tried to resume his duties. The result was that what the police described as 'disgruntled government employees' but what were probably police out of uniform, opened fire on his supporters, killing four and wounding 20.
'One day soon I will return,' says Mayor Paul, as he sits in a small office elsewhere in Port-au- Prince, his desk bare apart from a plaque expressing solidarity from Liverpool council. He says he is not in hiding, but sleeps in a different house every night.
Mr Paul says the military government has run out of money, and this is confirmed by diplomats. Two frightened government employees complained they had not been paid in two months. Pro- Aristide forces took over the Finance Ministry and found it looted. Last Friday they took over the general accounting office by breaking in the door with a battering ram, because the official put in charge by the military government had disappeared with the key.
The problem is that civilian ministries have never had much power in Haiti. The 8,000 soldiers and police, united in one body, have a monopoly of armed force and there is little sign of them giving it up. They are supported by a network of so-called attaches, or gunmen, who operate like the Sicilian Mafia, living on the fruits of petty extortion such as small bribes from taxi drivers or the peasants selling chickens in the market.
Five million out of 6 million Haitians still live outside the capital and here the army and police are in complete control. In the town of St Marc on the coast north of the capital, people cannot afford to make enemies with the local security men. When Lyonel Addee, a businessman from the town, was found on a beach 10 days ago, apparently beaten to death, his family and the local police agreed it was a clear case of suicide and quickly buried him.
The Governor's Island agreement says the army and police are to be split in two and soldiers will no longer be involved in local security. The police will be retrained, assisted by Canadian Mounties and French gendarmes. Officers with the worst reputations for killing and torture will theoretically be sent where they can do no damage.
Power in Haiti will be divided long after Fr Aristide returns. He has international and popular support but little organisation and no guns. The army and police - supported by the death squads - are not going to go out of business whatever the new constitutional arrangements. But President Aristide remains massively popular, with the reputation of a Messiah, and will not easily be marginalised. Once he is back, said a supporter, it will be 'like keeping a big tiger in a paper bag'.