The mass deployment of United States troops for the relief effort in Haiti is in full swing.

About 7000 US personnel are already stationed on naval ships off the Haitian coast or in the devastated capital, Port-au-Prince. A further 3000 troops are expected to arrive over the next few days.

On Tuesday afternoon, 12 helicopters from the US marines landed in the Presidential Palace compound and US forces have begun airdropping food supplies. The US relief operation is being co-ordinated from the Carl Vinson aircraft carrier. The United Nations has decided to deploy a further 3500 peacekeepers to Haiti.

At the moment, the troops are mostly occupied in keeping the peace, preventing looting and protecting Haitians from armed gangs. The US hopes to co-ordinate the international relief effort together with Canada and Brazil. The distribution of supplies, which is still partly being organised by the United Nations, is proving difficult.

One week after Haiti's devastating earthquake, survivors, often young children, are still being found among the wreckage. An estimated 250,000 people have been injured and one and a half million made homeless. The death toll could end up being as high as 200,000.

photos: US forces deployed in Haiti (YouTube)