Airport congestion was reduced on 18 January when the United Nations and US forces formally agreed to prioritise humanitarian flights over security reinforcement. By 14 January, more than 20 countries had sent military personnel to the country, with Canada, the United States, and the Dominican Republic providing the largest contingents. The supercarrier arrived at maximum possible speed on 15 January with 600,000 emergency food rations, 100,000 ten-litre water containers, and an enhanced wing of 19 helicopters; 130,000 litres of drinking water were transferred to shore on the first day. The helicopter carrier sailed with three large dock landing ships and two survey/salvage vessels, to create a "sea base" for the rescue effort. They were joined by the French Navy vessel "Francis Garnier" on 16 January, the same day the hospital ship and guided-missile cruiser left for Haiti. Another large French vessel was later ordered to Haiti, the amphibious transport dock "Siroco". International rescue efforts were restricted by traffic congestion and blocked roads. Although US Secretary of Defense Robert Gates had previously ruled out dropping food and water by air as too dangerous, by 16 January, US helicopters were distributing aid by drops to areas impossible to reach by land. In Jacmel, a city of 50,000, the mayor claimed that 70 percent of the homes had been damaged and that the quake had killed 300 to 500 people and left some 4,000 injured. The small airstrip suffered damage rendering it unusable for supply flights until 20 January. The Canadian navy vessel HMCS "Halifax" was deployed to the area on 18 January; the Canadians joined Colombian rescue workers, Chilean doctors, a French mobile clinic, and Sri Lankan relief workers who had already responded to calls for aid. About 64,000 people living in the three adjacent agricultural communities of Durissy, Morne a Chandelle, and Les Palmes were relatively unharmed because most of the people were working in the fields when the quakes struck. All their churches, chapels, and at least 8,000 homes were destroyed. On 17 January 2010, British search and rescue teams were the first to reach Léogane, the town at the epicenter of the quake. The Canadian ship HMCS "Athabaskan" reached the area on 19 January, and by 20 January some 250–300 Canadian personnel were assisting relief efforts in the town. By 19 January, staff of the International Red Cross had also managed to reach the town, which they described as "severely damaged ... the people there urgently need assistance."