International agencies are struggling to deliver aid to hundreds of thousands of earthquake survivors in Haiti. Latest reports say more than three million people need help.

Huge volumes of aid have been promised – and the United States is to send extra troops, as well a hospital ship.

Efforts are concentrating in the capital Port au Prince but the chronic lack of infrastructure is causing major problems with distribution.

Survivors are struggling to find food and drink and many bodies are still trapped in the rubble.